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Full text of "PHCC NSPC (2006): National Standard Plumbing Code, Illustrated"

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NOTICE OF INCORPORATION 

United States Legal Document 

J^" All citizens and residents are hereby advised that 
this is a legally binding document duly incorporated by 
reference and that failure to comply with such 
requirements as hereby detailed within may subject you 
to criminal or civil penalties under the law. Ignorance of 
the law shall not excuse noncompliance and it is the 
responsibility of the citizens to inform themselves as to 
the laws that are enacted in the United States of America 
and in the states and cities contained therein. "^& 

* * 

NAPHCC NSPC (2006, Illustrated), the National 
Standard Plumbing Code Illustrated, as incorporated 
and mandated by the State of Maryland in section 
09.20.01.01 of the COMAR. 




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2006 

NATIONAL STANDARD 

PLUMBING CODE 

ILLUSTRATED 








PUMBING-HEATING-COOUNG 
CONTRACTORS ASSOCIATION 



Published By 

PLUMBING-HEATING-COOLINGCONTRACTORS— 

NATIONAL ASSOCIATION 



All inquiries or questions relating to interpretation should be forwarded to 

Code Secretary 

1 80 S. Washington St., P.O. Box 6808 

Falls Church, VA22046-1 148 

1-800-813-7061 



©2006Plumbing-Heating-CoolingContractors-National Association 
To order additional books call 1 -800-533-7694 
(if calling from New Jersey call 1-800-652-7422) 



Second Printing - November 2006 



NATIONAL STANDARD 

PLUMBING CODE 

ILLUSTRATED 



Title: 

National Standard Plumbing Code Illustrated 
Scope: 

The development of a recommended code of plumbing practice, design, and installation, 
including the establishment of performance criteria predicated on the need for protection of 
health and safety through proper design, installation, and maintenance of plumbing systems. 
This scope excludes the development of specific standards related to the composition, 
dimensions, and/or mechanical and physical properties of materials, fixtures, devices, and 
equipment used or installed in plumbing systems. 

Purpose: 

To provide practices and performance criteria for the protection of health and safety through 
proper design of plumbing systems. 

Exceptions: 

In case of practical difficulty, unnecessary hardship or new developments, exceptions to the 
literal requirements may be granted by the authority having jurisdiction to permit the use of 
other devices or methods, but only when it is clearly evident that equivalent protection is 
thereby secured. 



FOREWORD 



Since its founding as the National Association of Master Plumbers in 1 883, the National Asso- 
ciation of Plumbing-Heating-Cooling Contractors has maintained a serious interest in plumbing 
standards, codes and good plumbing design practices. 

The Association published the NAMP "Standard Plumbing Code" in 1933 and furnished revised 
editions until 1942. NAPHCC participated in the development of special standards for war-time 
plumbing and later was represented on the National Plumbing Code Coordinating Committee, 
whose work ultimately resulted in the adoption of A40.8 as a standard or model plumbing code in 
1955. 

NAPHCC served as a sponsor in the early 1960's of the project which attempted to update the 
1955 document. This project was operated through the procedures of the American National 
Standards Institute. However, the A40.8 revision project was not completed because consensus 
could not be achieved. 

In order to provide local and state governments, code administrative bodies and industry with a 
modern, updated code, NAPHCC published the "National Standard Plumbing Code," in 197 1 , 
following the format and sequence of the A40.8 to provide for maximum convenience of users. 

With the June 1973 revision, the American Society of Plumbing Engineers joined this effort by 
co-sponsoring the National Standard Plumbing Code. ASPE maintained its co-sponsorship status 
until September, 1980. Upon ASPE's withdrawal of co-sponsorship, the Code Committee compo- 
sition was changed to include not only members of the contracting and engineering communities 
but also members of the inspection community. Contractors, engineers and inspectors now 
comprise the National Standard Plumbing Code Committee. 

The National Standard Plumbing Code Committee has worked closely with the plumbing industry 
to maintain a document of minimum requirements for plumbing systems that reflect current 
practices, materials, and techniques, consistent with public health and safety. 

However, the written requirements of a Code can sometimes be interpreted differently by differ- 
ent individuals. For this reason, the NSPC Committee developed the NSPC Illustrated, which 
includes explanatory comments and illustrations to demonstrate the intent of the various Code 
Sections. 

The Committee also realizes that despite the countless hours of preparation and review, perfection 
may not have been achieved in this document. For this reason, please send any questions, com- 
ments, suggestions, or problems to the Code Secretary, Plumbing-Heating-Cooling Contractors - 
National Association, P.O. Box 6808, Falls Church, VA 22046- 1 148. 

Comments on Code Text 

The comments following the various Sections of the Code text are intended to explain the intent of 
that Section of the Code. The comments themselves are not Code requirements but are intended 
to supplement the Code and provide guidance toward its interpretation. 



Figures and Figure Notes 

The illustrations (figures) are intended to graphically demonstrate the intent or provide an example 
of the referenced definition or Code Section. The illustrations are based only on the referenced 
definition or Code Section and do not necessarily include all details of the complete installation, 
such as pipe sizes, specific pipe fittings, required pipe supports, required cleanouts, and other 
details that are not part of the definition or Code Section being illustrated. The illustrations must 
not be used to justify work that does not comply with all requirements of the Code. 

The illustrations are not intended to restrict installations to the arrangement shown. In many 
cases, the illustrations show only one example or a typical example of an acceptable arrangement. 
Any arrangement that meets the intent of the referenced Code Section is acceptable. 



IV 



Introductory Note 



The material presented in this Code does not have legal standing unless it is adopted by 
reference, or by inclusion, in an act of state, county, or municipal government. Therefore, 
administration of the provisions of this Code must be preceded by suitable legislation at the 
level of government where it is desired to use this Code. 

In some places in this Code, reference is made to "Authority Having Jurisdiction." The 
identity of an Authority Having Jurisdiction will be established by the act which gives legal 
standing to the Code provisions. 

Meetings for purposes of review and revision are scheduled each year with proper public 
notices. 

Suggestions and requests for revisions can be made by any interested party and should 
be submitted on the special forms provided by the Committee. 

Personal appearance before the Committee for a hearing on any Code matter can be had 
by interested parties after a request in writing. 

In the course of revision, certain outdated sections have been deleted. In order to 
maintain consistency and perpetuity of the numbering system, those deleted sections and 
numbers have been removed from this printed text, or placed in reserve. 



All changes from the previous edition of this Code are 
marked by a vertical line in the margin. 



2006 National Standard Plumbing Code Committee 



J. Richard Wagner, PE, Chairman 

The Poole & Kent Corporation 
4530 Hollins Ferry Rd 
Baltimore, MD 212-27-4670 
Phone: (410)247-2200 
Fax: (410)247-2331 
Dick_Wagner@emcorgroup.com 

Charlie Chalk 

E-B-L Engineers, LLC 
8005 Harford Rd 
Baltimore,MD21234-5701 
Phone:(410)668-8000 
Fax: (410)668-8001 
cchalk@eblengineers.com 

William Chamberlin 

ChamberlinPlbg.&Htg Company 
P.O. Box 390 

1274 Route 130 South 
Windsor, NJ 08561 
Phone:(609)448-1848 
Fax: (609)448-8683 

Michael J. Kastner 

Kastner Plumbing & Pleating 
12630 Friendship Road 
West Friendship, MD 21794 
Phone: (301)725-5000 
Fax: (410)442-7626 
mjkjr@aol.com 

Leon LaFreniere 

City of Manchester, Dept. of Buildings 

One City Plaza 

Manchester, NH 03101 

Phone: (603)624-6475 

Fax: (603)624-6324 

llafreniere@ci.manchester.nh.us 

FrankR.Maddalon 

F. R. Maddalon Plumbing & Heating 

1550 Sylvan Ave 

Hamilton, NJ 08610-4461 

Phone:(609)587-8317 

Fax: (609)587-9848 

fmaddalon@aol.com 

Thomas C. Pitcherello 

NJ Department of Community Affairs 

Codes Assistance Unit 

101 S. Broad Street, PO Box 802 

Trenton, NJ 08625-0802 

Phone: (609)984-7609 

Fax: (609)984-7717 

tpitcherello@dca.state.nj.us 



Luis A. Rodriguez, C.P.D. 

KSI Professional Engineers 

P.O. Box 628 

Farmingdale, N J 07727 

Phone:(732)938.2666 

Fax: (732)938.2661 

E-mail: lrodriguez@ksi-pe.com 

Ronald W.Stiegler 

Phoenix Plumbers, Inc. 
5320-J Enterprise St. 
Eldersburg,MD 21784-9313 
Phone: (410)781-3000 
Fax: (410)781-6826 
phoenixplumbers@erols.com 

Alex Tuccia rone 

Old Bridge Plumbing Inspector 

58 Lear Cl 

East Brunswick, NJ 088 16-1853 

Phone:(732)721-56002420 

Fax: (732)607-7912 

aj tuccia@oldbridge. com 

Jerry Van Pelt, CIPE 

Clive Samuels & Associates, Inc. 

4000 Route 66 

Tinton Falls, NJ 07753 

Phone: (732)643-9666 

Fax: (732)643-9667 

jvp@csa-ce.com 

Dave Viola 

Plumbing Manufacturers Institute 
1 340 Remington Rd., Suite A 
Schaumburg, IL 601 73 
Phone:(847)884-9764 
Fax: (847)884-9775 
dviola@pmihome.org 

Robert Kordulak 
NSPC Secretariat 

The Arkord Company 

206 1st Ave., #603 
Belmar,NJ 077 19-2006 
Phone: (732)681-5400 
Fax: (732)681-5047 
bkord3 565 @optonline.net 

FrankR.Maddalon 
Executive Committee Liaison 

F. R. Maddalon Plumbing & Heating 

1550 Sylvan Ave 

Hamilton, N J 08610-4461 

Phone:(609)587-8317 

Fax: (609)587-9848 

fmaddalon@aol.com 



Julie A.Turner 

StaffLiaison 

Plumbing-Heating-Cooling Contrac- 
tors-National Association 
180 S.Washington St., 
Falls Church, VA 22046 
(703) 237-8 1 00 or (800) 533-7694 
Fax:(703)237-7442 
e-mail: turner@naphcc.org 
URL: http://www.phccweb.org 



VI 



Contents 



Title, Scope, Purpose, Exceptions i 

Foreword iii 

Introductory Note v 

Committee Members vi 

Administration 1 

Basic Principles 9 

Chapter 1 — Definitions 13 

Chapter 2 — General Regulations 65 

Chapter 3 — Materials 83 

Chapter 4 — Joints and Connections Ill 

Chapter 5 — Traps, Cleanouts and Backwater Valves 135 

Chapter 6 — Interceptors 151 

Chapter 7 — Plumbing Fixtures, Fixture Fittings and Plumbing Appliances 161 

Chapter 8 — Hangers and Supports 193 

Chapter 9 — Indirect Waste Piping and Special Wastes 197 

Chapter 10 — Water Supply and Distribution 209 

Chapter 11 — Sanitary Drainage Systems 251 

Chapter 12 — Vents and Venting 273 

Chapter 13 — Storm Water Drainage 311 

Chapter 14 — Special Requirements for Health Care Facilities 325 

Chapter 15 — Tests and Maintenance 331 

Chapter 16 — Regulations Governing Individual Sewage Disposal 

Systems for Homes and Other Establishments Where 

Public Sewage Systems Are Not Available 335 

Chapter 17 — Potable Water Supply Systems 351 

Chapter 18 — Mobile Home & Travel Trailer 

Park Plumbing Standards 359 

Appendix A — Sizing Storm Drainage Systems 367 

AppendixB — Sizing the Building Water Supply System 375 

AppendixC — Conversions: Customary Units to Metric 411 

Appendix D — Determining the Minimum Number ofRequired 

Plumbing Fixtures 413 

AppendixE — Special Design Plumbing Systems 419 

AppendixF — Requirements ofthe Authority Having Jurisdiction 427 

AppendixG — Gray water Recycling Systems 429 

AppendixH — Installation of Medical Gas and Vacuum Piping Systems 433 

Appendixl — Fixture Unit Value Curves for Water Closets 435 

Appendix J — Sizing Grease Interceptors 439 



AppendixK — Flow in Sloping Drains 441 

AppendixL — An Acceptable Brazing Procedure for General Plumbing 445 

Index — Alphabetical Index 453 



\m 




ADM 1.1 TITLE 

The regulations contained in the following chapters and sections shall be known as the "National Standard 
Plumbing Code" and may be cited as such, and hereinafter referred to as "this Code". 

ADM 1.2 SCOPE 

The provisions of this Code shall apply to every installation, including the erection, installation, alteration, reloca- 
tion, repair, replacement, addition to, use or maintenance of the plumbing system as defined within this Code. 

ADM 1.3 PURPOSE 

This Code establishes the minimum requirements and standards pertaining to the design, installation, use and 
maintenance of the plumbing system as defined within this Code. 

ADM 1.4 APPLICABILITY 

1.4.1 Addition or Repair 

Additions, alterations or repairs in compliance to this Code may be made to any existing plumbing system 
without requiring the existing installation to comply with all the requirements of this Code. Additions, alterations or 
repairs shall not cause an existing system to become unsafe, insanitary or overloaded. 

1.4.2 Existing Plumbing Installation 

Plumbing systems that were lawfully installed prior to the adoption of this Code may continue their use, mainte- 
nance or repairs, provided the maintenance or repair is in accordance with the original design, location, and no 
hazard has been created to life, health or property by such plumbing system. 

1.4.3 Existing Use 

The lawful use of any plumbing installation, appliances, fixtures, fittings and appurtenances may have their use 
continued, provided no hazards to life, health or property have been created by their continued use. 

1.4.4 Maintenance and Repairs 

The maintenance of all plumbing systems, materials, appurtenances, devices or safeguards, both existing and 
new, shall be maintained in a safe and proper condition. The owner, or his designated agent, shall be responsible 
for the maintenance of the plumbing system. 

Minor repairs to or replacement of any existing systems are permitted, provided they are made in the same 
manner and arrangement as the original installation and are approved. 

1.4.5 Change of Building Use 

The plumbing systems of any building or structure that is proposed for a change in use or occupancy shall 
comply to all the requirements of this Code for the new use or occupancy. 

1.4.6 Moved Buildings or Structures 

The plumbing system in any building or structure to be moved into this jurisdiction shall comply with the provi- 
sions of this Code for new construction. 



2006 National Standard Plumbing Code-Illustrated 



1.4.7 Special Historic Buildings 

The provisions of this Code relating to the additions, alterations, repair, replacement or restoration of those 
structures designated as historic buildings shall not be mandatory when such work is deemed to be safe and in the 
public interest of health, safety and welfare by the Authority Having Jurisdiction. 

1.4.8 Appendices 

The provisions in the appendices are intended to supplement the requirements of this Code and are considered 
to be part of this Code when adopted by the Authority Having Jurisdiction 

ADM 1.5 APPROVALS 

1.5.1 Alternates 

The provisions cited in this Code are not intended to prevent the use of any material or method of installation 
when it is determined to meet the intent of this Code and approved by the Authority Having Jurisdiction 

1.5.2 Authority Having Jurisdiction 

The Authority Having Jurisdiction may approve any such alternate material or method of installation not ex- 
pressly conforming to the requirements of this Code, provided it finds the proposed material or method of installa- 
tion is at least the equivalent of that required in the Code or that the alternate material or method of installation 
conforms to other nationally accepted plumbing standards. A record of such approval shall be kept and shall be 
available to the public. 

1.5.3 Tests Required 

The Authority Having Jurisdiction shall require sufficient evidence to substantiate any claims made regarding the 
equivalency of any proposed alternate material or method of installation. When the Authority Having Jurisdiction 
determines that there is insufficient evidence to substantiate the claims, it may require tests to substantiate the 
claims be made by an approved testing agency at the expense of the applicant. 

1.5.4 Test Procedure 

The Authority Having Jurisdiction shall require all tests be made in accordance with approved standards; but, in 
the absence of such standards, the Authority Having Jurisdiction shall specify the test procedure. 

1.5.5 Retesting 

The Authority Having Jurisdiction may require any tests to be repeated if, at any time, there is reason to believe 
that any material or method of installation no longer conforms to the requirements on which the original approval 
was based. 

ADM 1.6 ORGANIZATION AND ENFORCEMENT 

1.6.1 Authority Having Jurisdiction 

The Authority Having Jurisdiction shall be the individual official, board, department or agency duly appointed by 
the jurisdiction as having the authority to administer and enforce the provisions of this Code as adopted or 
amended. 

1.6.2 Deputies 

In accordance with the procedures set forth by the jurisdictional authority, the Authority Having Jurisdiction may 
appoint such assistants, deputies, inspectors or other designated employees to carry out the administration and 
enforcement of this Code. 



2006 National Standard Plumbing Code-Illustrated 



1.6.3 Right of Entry 

When inspections are required to enforce the provisions of this Code, or there is reasonable cause to believe 
there exists in any building, structure or premises, any condition or violation of this Code causing the building 
structure or premises to be unsafe, insanitary, dangerous or hazardous, the Authority Having Jurisdiction or its 
designated representative may enter such building, structure or premises at reasonable times to inspect or perform 
the duties imposed by this Code. When the building, structure or premises are occupied, proper credentials shall be 
presented to the occupant when entry is required. In the event the building, structure or premises is unoccupied 
and entry is required, a reasonable effort shall be made to locate the owner or his agent in charge of such building 
structure or premises. In the event the occupant or owner of such building, structure or premises refuses entry the 
Authority Having Jurisdiction shall have recourse to the remedies provided by law to gain entry. 

1.6.4 Stop Work Order 

Upon notice from the Authority Having Jurisdiction, work being done on any building, structure or premises 
contrary to the provisions of this Code, or in an unsafe and dangerous manner, shall be stopped immediately The 
stop work notice shall be m writing, served on the owner of the property, or his agent, or to the person doing such 
work. It shall state the conditions under which the Authority Having Jurisdiction may grant authorization to 
proceed with the work. 

1.6.5 Authority to Condemn 

When the Authority Having Jurisdiction determines that any plumbing system or portion thereof that is regulated 
by this Code has become insanitary or hazardous to life, health or property, it shall order in writing that such 
plumbing system or portion thereof be repaired, replaced or removed so as to be in code compliance The written 
order shall fix a reasonable time limit for the work to be brought into code compliance, and no person shall use the 
condemned plumbing system until such work is complete and approved by the Authority Having Jurisdiction. 

1.6.6 Authority to Abate 

Any plumbing system, or portion thereof that is found to be insanitary or constitute a hazard to life health or 
property is hereby declared to be a nuisance. Where a nuisance exists, the Authority Having Jurisdiction shall 
require the nuisance to be abated and shall seek such abatement in the manner prescribed by law. 

1.6.7 Liability 

The Authority Having Jurisdiction, or any individual duly appointed or authorized by the Authority Having 
Jurisdiction to enforce this Code, acting in good faith and without malice, shall not thereby be rendered personally 
liable for any damage that may occur to persons or property as a result of any act, or by reason of any act or 
omission in the lawful discharge of his duties. Should a suit be brought against the Authority Having Jurisdiction or 
duly appointed representative because of such act or omission, it shall be defended by legal counsel provided by 
this jurisdiction until final termination of the proceedings. 

1.6.8 Work Prior to Permit 

Where work for which a permit is required by this Code is started prior to obtaining the prescribed permit the 
applicant shall pay a double fee. In the event of an emergency where it is absolutely necessary to perform the 
plumbing work immediately, such as nights, weekends or holidays, said fee shall not be doubled if a permit is 
secured at the earliest possible time after the emergency plumbing work has been performed. 

ADM 1.7 VIOLATIONS AND PENALTIES 

1.7.1 Violations 

It shall be unlawful for any individual, partnership, firm or corporation to, or cause to, install, construct, erect, 
alter, repair, improve, convert, move, use or maintain any plumbing system in violation of this Code. 



2006 National Standard Plumbing Code-Illustrated 



1.7.2 Penalties 
Any individual, partnership, firm or corporation who shall violate or fail to comply with any of the requirements 

of this Code shall be deemed guilty of a , and if convicted, shall be punishable by a fine or imprisonment 

or both as established by this jurisdiction. Each day during which a violation occurs or continues, shall constitute a 
separate offense. 

ADM 1.8 PERMITS 

1.8.1 Permits Required 

It shall be unlawful for any individual, partnership, firm or corporation to commence, or cause to commence, any 
installation, alteration, repair, replacement, conversion or addition to any plumbing system, or part thereof, regulated 
by this Code, except as permitted in Section 1 .8.2, without first obtaining a plumbing permit for each separate 
building or structure, on forms prepared and provided by the Authority Having Jurisdiction. 

1.8.2 Permits Not Required for the Following 

a. Permits shall not be required for the following work: 

1. The stoppage of leaks in drains, soil, waste or vent pipes. However, should the defect necessitate removal 
and replacement with new material, it shall constitute new work and a permit shall be obtained and inspection 
made as required in this Code. 

2. The clearing of stoppages. 

3. The repairing of leaks in valves or fixtures. 

4. The removing and reinstallation of a water closet for a cleanout opening provided the reinstallation does not 
require replacement or rearrangement of valves, pipes or new fixtures. 

b. Exemptions from obtaining a permit required by this Code shall not be construed as to authorize any work to 
be performed in violation of this Code. 

ADM 1.9 PROCESS FOR OBTAINING PERMITS 

1.9.1 Application 

a. Applications for a permit shall be made in writing by the person, or his agent, proposing to do such work 
covered by the permit. The applicant shall file such application in writing on a form prepared and provided by the 
Authority Having Jurisdiction. Every such permit shall: 

1 . Describe in detail the work to be done for which the permit was obtained. 

2. Describe in detail the parcel of land on which the proposed work is to be done by legal description, street 
address or other means to definitely locate the site or building where the work is to be performed. 

3. List the type of occupancy or use. 

4. Provide plans, drawings, diagrams, calculations or other data as required by Section 1 .9.2. 

5. Be signed by the person or agent making application. 

6. Provide any other information the Authority Having Jurisdiction may require. 

1.9.2 Plans 

Two or more sets of plans shall be submitted with each permit application. The plans shall contain all the 
engineering calculations, drawings, diagrams and other data as required for approval. The Authority Having 
Jurisdiction may also require that the plans, drawings, diagrams and calculations be designed by an engineer and/or 
architect licensed by the state in which the work is to be performed. 

Except that the Authority Having Jurisdiction may waive the submission of plans and other data, provided it is 
determined that the nature of the work covered by the permit does not require plan review to obtain code compliance. 



2006 National Standard Plumbing Code-Illustrated 



1.9.3 Specifications 

All specifications required to be on the plans shall be drawn to scale and sufficiently clear to indicate the nature, 
location and extent of the proposed work so as to show how it will conform to the requirements of this Code. 

1.9.4 Permit Issuance 

If, after reviewing the plans and specifications, the Authority Having Jurisdiction finds that they are complete 
and conform to the requirements of this Code, it shall authorize a permit to be issued upon payment of all the fees 
specified in Section 1.10.1. 

1.9.5 Approved Plans 

When the Authority Having Jurisdiction issues a permit and plans were required, it shall endorse, either in 
writing or stamp the plans "APPROVED", and all work shall be done in accordance with the plans without 
deviation. 

1.9.6 Plans Retention 

The Authority Having Jurisdiction shall retain one set of approved plans until final approval of the work con- 
tained therein. One set of approved plans shall be returned to the applicant and this set of approved plans shall be 
kept on the job site at all times until final approval of the work contained therein. 

1.9.7 Permit Validity 

The issuance of a permit by the Authority Having Jurisdiction is not and shall not be construed to be authoriza- 
tion or approval of any violation of the requirements of this Code. Any presumption of a permit to be authorization 
to violate or cancel any provisions of this Code shall be invalid. The issuance of a permit based on plans submitted 
shall not prevent the Authority Having Jurisdiction from requiring the correction of any errors in the plans or 
preventing the progress of the construction when it is in violation of any provision of this Code. 

1.9.8 Permit Expiration 

Every permit issued by the Authority Having Jurisdiction, in accordance with the provisions of this Code, shall 
expire by limitation and become null and void when such work authorized by the permit has not commenced within 
days from the date of issuance or if such work is suspended or abandoned for a period of days after com- 
mencement of such work. In order for such work to recommence, a new permit shall be obtained and a fee of 
percent of the original permit fee shall be charged, provided no changes have been made or will be made to the 
original plans as submitted. The Authority Having Jurisdiction may grant an extension to any permit provided the 
request is in writing by the permittee stating the reason or circumstances that prevented him from completing such 
work as required by this Code. 

1.9.9 Revocation or Suspension 

At any time, the Authority Having Jurisdiction may suspend or revoke a permit issued in error or on the basis of 
incorrect information submitted or in violation of any section of this Code. The suspension or revocation of such 
permit shall be in written form by the Authority Having Jurisdiction stating the reason or purpose of such suspen- 
sion or revocation. 

ADM 1.10 PERMITS 

1.10.1 Fees Schedule 

The permit fees for all plumbing work shall be set forth by the Authority Having Jurisdiction of the jurisdiction 
having authority. 



2006 National Standard Plumbing Code-Illustrated 



1.10.2 Plan Review Fees 

When plans are reviewed as a requirement prior to issuance of a permit, the fee shall be equal to percent 

of the total permit fee as set forth in Section 1.10.1. 

1.10.3 Plan Review Expiration 

Permit application and plan review for which no permit is issued shall expire by limitation within days 

following the date of application. All plan review fees shall be forfeited and the plans may be destroyed by the 
Authority Having Jurisdiction or returned to the applicant. 

1.10.4 Work Without a Permit 

When any plumbing work is commenced without first obtaining a permit from the Authority Having Jurisdiction, 
an investigation of such work shall be made before a permit may be issued. The investigation fee shall be collected 
whether or not a permit is then or subsequently issued. Any investigation fee shall equal the amount of the permit 
fee, if a permit were to be issued in accordance with this Code. If the investigation fee is collected, it shall not 
exempt any person from compliance or penalties set forth in this Code. 

1.10.5 Refunding of Fees 

Any fee collected by the Authority Having Jurisdiction that was erroneously paid or collected may be refunded, 

provided not more than percent of the fee payment shall be refunded when no work has been done. Any 

request for the refunding of any fee shall be in writing by the applicant no later than days after the date of fee 

payment. 



ADM 1.11 INSPECTIONS 

1.11.1 Required Inspections 

All new plumbing systems, and parts of existing systems that require a permit shall be tested and inspected by 
the Authority Having Jurisdiction prior to being covered or concealed. Where any such work has been covered or 
concealed, the Authority Having Jurisdiction shall require such work exposed for inspection and testing. All 
equipment, material and labor required for testing the plumbing system shall be furnished by the permittee. The 
Authority Having Jurisdiction shall not be liable for any expense incurred by the removal or replacement of materi- 
als required to permit inspection or testing. Such expense is the responsibility of the permittee. Upon completion of 
the rough plumbing installation, prior to covering or concealing any such work, the Authority Having Jurisdiction 
shall inspect the work and any such test, as prescribed hereinafter, to disclose any leaks or defects. After comple- 
tion of the plumbing system and the plumbing fixtures are set and their traps filled with water, a final inspection 
shall be conducted as required by this Code. Additional inspections may be required when alternate materials or 
methods of installation are approved by the Authority Having Jurisdiction. 

1.11.2 Exception: 

For moved-in or relocated structures, minor installations and repairs, the Authority Having Jurisdiction may 
make other such inspections or tests as necessary to assure that the work has been performed and is safe for use 
in accordance with the intent of this Code. 

1.11.3 Use of Existing Plumbing 

The operation of any plumbing installation to replace existing systems or fixtures serving an occupied portion of 
any building or structure shall not be considered by the requirements of this Code to prohibit such operation, 
provided a request for inspection has been made to the Authority Having Jurisdiction within 48 hours of such work 
and before any such work is covered or concealed. 



2006 National Standard Plumbing Code-Illustrated 



1.11.4 System Testing 

All new plumbing systems and parts of existing systems shall be tested and approved as required elsewhere in 
this Code. 

1.11.5 Requests for Inspection 

The Authority Having Jurisdiction shall be notified by the person doing the work, authorized by the permit, that 
such work is subjected to the required tests and is ready for inspection. The method of request, whether in writing 
or by telephone, shall be established by the Authority Having Jurisdiction. 

It shall be the duty of the permittee doing the work authorized by a permit to provide reasonable access and 
means for accomplishing proper inspections. 

1.11.6 Other Inspections 

The Authority Having Jurisdiction may require other inspections, in addition to those required by this Code, of 
any plumbing work in order to ascertain compliance with the requirements of this Code. 

1.11.7 Reinspection Fees 

a. The assessment of a reinspection fee may be required for any of the following: 

1. For any portion of work not completed for which inspection was requested. 

2. For any required corrections that have not been completed and for which reinspection was requested. 

3. For not having the approved plans on site and readily available to the inspector. 

4. Failure to provide access for inspection on the date inspection was requested. 

5. Deviation from the approved plans that would require reapproval of the Authority Having Jurisdiction. 

6. Failure to provide correct address. 

b. This provision is intended to control the practice of calling for inspections prior to having work ready for 
inspection and not for the first time job rejection for not complying with the installation requirements. 

c. Upon the assessment of a reinspection fee, the applicant shall pay the reinspection fee in accordance with 
Section 1 .10.1 and no additional inspections shall be performed until all fees have been paid. 

ADM 1.12 FINAL CONNECTIONS 

1.12.1 Energy or Fuel 

It shall be unlawful for any person to make, or cause to make, any connection to any source of energy or fuel to 
any plumbing system or equipment regulated by this Code prior to the approval of the Authority Having Jurisdic- 
tion. 

1.12.2 Water and Sewer 

It shall be unlawful for any person to make, or cause to make, any connection to any water supply or sewer 
system to any plumbing system or equipment regulated by this Code prior to the approval of the Authority Having 
Jurisdiction. 

1.12.3 Temporary Connection 

By authorization of the Authority Having Jurisdiction, a temporary connection may be made to any plumbing 
equipment to a source of energy or fuel for testing purposes only. 

ADM 1.13 UNCONSTITUTIONALITY 

Should any chapter, section, subsection, sentence, clause or phrase of this Code be held for any reason as 
unconstitutional, such decision shall not affect the validity of the remaining chapters, sections, subsections, sen- 
tences, clause or phrases of this Code. 



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2006 National Standard Plumbing Code-Illustrated 




This Code is founded upon certain basic principles of environmental sanitation and safety through properly 
designed, acceptably installed, and adequately maintained plumbing systems. Some of the details of plumbing 
construction may vary but the basic sanitary and safety principles desirable and necessary to protect the health of 
the people are the same everywhere. 

The establishment of trade jurisdictional areas is not within the scope of this Code. This inclusion of material, 
even though indicated as approved for purposes of this Code, does not infer unqualified endorsement as to its 
selection or serviceability in any or every installation. 

As interpretations may be required, and as unforeseen situations arise which are not specifically covered in this 
Code, the twenty-two principles which follow shall be used to define the intent. 

Principle No. 1— ALL OCCUPIED PREMISES SHALL HAVE POTABLE WATER 

All premises intended for human habitation, occupancy, or use shall be provided with a supply of potable water. 
Such a water supply shall not be connected with unsafe water sources, nor shall it be subject to the hazards of 
backflow. 

Principle No. 2— ADEQUATE WATER REQUIRED 

Plumbing fixtures, devices, and appurtenances shall be supplied with water in sufficient volume and at pressures 
adequate to enable them to function properly and without undue noise under normal conditions of use. 

Principle No. 3— HOT WATER REQUIRED 

Hot water shall be supplied to all plumbing fixtures which normally need or require hot water for their proper use 
and function. 

Principle No. 4— WATER CONSERVATION 

Plumbing shall be designed and adjusted to use the minimum quantity of water consistent with proper performance 
and cleaning. 

Principle No. 5— SAEETY DEVICES 

Devices for heating and storing water shall be so designed and installed as to guard against dangers from explosion 
or overheating. 

Principle No. 6— USE PUBLIC SEWER WHERE AVAILABLE 

Every building with installed plumbing fixtures and intended for human habitation, occupancy, or use, and located 
on premises where a public sewer is on or passes said premises within a reasonable distance, shall be connected to 
the sewer. 

Principle No. 7— REQUIRED PLUMBING FIXTURES 

Each family dwelling unit shall have at least one water closet, one lavatory, one kitchen-type sink, and one bathtub 
or shower to meet the basic requirements of sanitation and personal hygiene. 

All other structures for human habitation shall be equipped with sufficient sanitary facilities. Plumbing fixtures shall 
be made of durable, smooth, non-absorbent and corrosion resistant material and shall be free from concealed 
fouling surfaces. 



2006 National Standard Plumbing Code-Illustrated 



Principle No. 8— DRAINAGE SYSTEM 

The drainage system shall be designed, constructed, and maintained to guard against fouling, deposit of solids and 
clogging, and with adequate cleanouts so arranged that the pipes may be readily cleaned. 

Principle No. 9— DURABLE MATERIALS AND GOOD WORKMANSHIP 

The piping of the plumbing system shall be of durable material, free from defective workmanship and so designed 
and constructed as to give satisfactory service for its reasonable expected life. 

Principle No. 10— FIXTURE TRAPS 

Each fixture directly connected to the drainage system shall be equipped with a liquid seal trap. 

Principle No. 11 —TRAP SEALS SHALL BE PROTECTED 

The drainage system shall be designed to provide an adequate circulation of air in all pipes with no danger of 
siphonage, aspiration, or forcing of trap seals under conditions of ordinary use. 

Principle No. 12— EXHAUST FOUL AIR TO OUTSIDE 

Each vent terminal shall extend to the outer air and be so installed as to minimize the possibilities of clogging and 
the return of foul air to the building. 

Principle No. 13— TEST THE PLUMBING SYSTEM 

The plumbing system shall be subjected to such tests as will effectively disclose all leaks and defects in the work 
or the material. 

Principle No. 14— EXCLUDE CERTAIN SUBSTANCES FROM THE PLUMBING SYSTEM 

No substance which will clog or accentuate clogging of pipes, produce explosive mixtures, destroy the pipes or 
their joints, or interfere unduly with the sewage-disposal process shall be allowed to enter the building drainage 
system. 

Principle No. 15— PREVENT CONTAMINATION 

Proper protection shall be provided to prevent contamination of food, water, sterile goods, and similar materials by 
backfiow of sewage. When necessary, the fixture, device, or appliance shall be connected indirectly with the 
building drainage system. 

Principle No. 16— LIGHT AND VENTILATION 

No water closet or similar fixture shall be located in a room or compartment which is not properly lighted and 
ventilated. 

Principle No. 17— INDIVIDUAL SEWAGE DISPOSAL SYSTEMS 

If water closets or other plumbing fixtures are installed in buildings where there is no sewer within a reasonable 
distance, suitable provision shall be made for disposing of the sewage by some accepted method of sewage 
treatment and disposal. 



1 2006 National Standard Plumbing Code-Illustrated 



Principle No. 18— PREVENT SEWER FLOODING 

Where a plumbing drainage system is subject to backflow of sewage from the public sewer or private disposal 
system, suitable provision shall be made to prevent its overflow in the building. 



Principle No. 19— PROPER MAINTENANCE 

Plumbing systems shall be maintained in a safe and serviceable condition from the standpoint of both mechanics 
and health. 



Principle No. 20— FIXTURES SHALL BE ACCESSIBLE 

All plumbing fixtures shall be so installed with regard to spacing as to be accessible for their intended use and for 
cleaning. 



Principle No. 21— STRUCTURAL SAFETY 

Plumbing shall be installed with due regard to preservation of the strength of structural members and prevention of 
damage to walls and other surfaces through fixture usage. 

Principle No. 22— PROTECT GROUND AND SURFACE WATER 

Sewage or other waste shall not be discharged into surface or sub-surface water unless it has first been subjected 
to some acceptable form of treatment. 



2006 National Standard Plumbing Code-Illustrated 1 1 



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2006 National Standard Plumbing Code-Illustrated 






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III 




Definitions 



1.1 GENERAL 



For the purpose of this Code, the following terms shall have the meaning indicated in this chapter. No attempt is 
made to define ordinary words that are used in accordance with their established dictionaiy meaning, except 
where it is necessary to define their meaning as used in this Code to avoid misunderstanding. 

1.2 DEFINITION OF TERMS 

Accessible and Readily Accessible: 

Accessible: access thereto without damaging building surfaces, but that first may require the removal of an 
access panel, door or similar obstructions with the use of tools. See Figure 1.2.1 

Readily accessible: access without requiring the use of tools for removing or moving any panel, door or 
similar obstruction. See Figure 1.2.1 




VALVE IS ACCESSIBLE IF LATCH 
IS SCREWDRIVER-OPERATED 



VALVE IS READILY ACCESSIBLE IF 
LATCH IS HANDLE-OPERATED 



Figure 1.2.1 
AN EXAMPLE OF ACCESSIBLE AND READILY ACCESSIBLE 

Acid Waste: See "Special Wastes" 

Adopting Agency (See also "Authority Having Jurisdiction") The agency, board or authority having the 
duty and power to establish the plumbing code that will govern the installation of all plumbing work to be per- 
formed in the jurisdictions. 

Air Break (drainage system): A piping arrangement in which a drain from a fixture, appliance, or device 
discharges into a fixture, receptor, or interceptor at a point below the flood level rim and above the trap seal of the 
receptor.See Figure 1.2.2 and Section 9.1.3 



2006 National Standard Plumbing Code-Illustrated 



13 



Comment: Air breaks are permitted where backflow cannot occur due to back-siphonage. 



FLOOD LEVEL RIM 




INDIRECT WASTE PIPE 
TERMINATING BELOW 
FLOOD LEVEL RIM 
OF RECEPTOR 



AIR BREAK 

I 
TOP OF TRAP SEAL 

L 



STANDPIPE- 



^M 



\ 



DISCHARGE HOSE 



CLOTHES 
WASHER 



A. AIR BREAK IN FLOOR SINK 



B. AIR BREAK IN CLOTHES 
WASHER STANDPIPE 



Figure 1.2.2 
AIR BREAKS 



Air Chamber: A pressure surge absorbing device operating through the compressibility of air. 



Comment: The Code no longer mentions air chambers. Air chambers were usually field-fabricated and 
were initially filled with air at atmospheric pressure. There was direct contact between the captive air 
and water, which permitted the air to be absorbed into the water over a period of time. The Code now 
calls for water hammer arrestors, which are pre-charged with compressed air or gas and have bellows or 
pistons that separate the air or gas from the water. See Figure 1.2.3. 



NOTE 




WATER HAMMER ARRESTOR 



3 — TO FIXTURE OR APPLIANCE 

WITH QUICK CLOSING VALVE 



BRANCH SHUTOFF VALVE 



NOTES: 

1 . For maximum effectiveness, the water hammer arrestor should be oriented so that the direction of 
the shock wave caused by the quick-closing valve is into the arrestor. Refer to the manufacturer's 
instructions. 

2. The number of elbows upstream from the water hammer arrestor should be minimized. Each elbow 

represents a point of shock and potential failure. 

Figure 1.2.3 
A WATER HAMMER ARRESTOR 



14 



2006 National Standard Plumbing Code-Illustrated 



Air Gap (drainage system): The unobstructed vertical distance through the free atmosphere between the outlet 
of the waste pipe and the flood level rim of the receptor into which it is discharging. See Figure 1.2.4 



Comment: Air gaps are required where back/low can occur due to back-siphonage. 



AIR GAP 




INDIRECT WASTE PIPE 
r RECEPTOR 



L-O 



Figure 1.2.4 
AN AIR GAP FOR INDIRECT WASTE PIPING 



Air Gap (water distribution system): The unobstructed vertical distance through the free atmosphere between 
the lowest opening from any pipe or faucet supplying water to a tank, plumbing fixture or other device and the 
flood level rim of the receptor. See Figure 1.2.S 



Comment #1: The minimum required air gap distance is based on the effective opening of the water 
supply outlet. The air gap must be increased if the outlet is close to walls or other vertical surfaces. See 
Section 10.5.2 and Table 1 0. 5. 2. 

Comment #2: If air is being drawn into the tub spout by a vacuum in the water supply piping, waste 
water at the flood level rim of the fixture will tend to be lifted upward towards the spout opening by the 
flow of air. The water will lift higher if the spout opening is close to a wall. 



TUB SPOUT 



FLOOD LEVEL RIM AIR GAP 
OF BATHTUB 




Figure 1.2.5 
AN AIR GAP FOR A POTABLE WATER OUTLET 



2006 National Standard Plumbing Code-Illustrated 



15 



Anchors: See "Supports." See Chapter 8 

Anti-scald Valve: See "Water Temperature Control Valve." See Section 10.15.6 

Approved: Accepted or acceptable under an applicable standard stated or cited in this Code, or accepted as 
suitable for the proposed use under procedures and powers of the Authority Having Jurisdiction as defined in 
Section 3.12. See Sections 3.1.1, 3.1.2, 3.1.3, and 3.12 

Area Drain: A receptor designed to collect surface or storm water from an open area. See Figures 1.2.6 and 
13.1.6 



WINDOW WELL 
DRAIN LESS 
THAN10S.F 
(Section 13.1.7) 



TO AN APPROVED 
POINT OF DISPOSAL 




"J"^ -""» AREAWAY DRAIN 

LESS THAN 100 S.F. 
(Section 13.1.6) 



Figure 1.2.6 
AREA DRAINS IN WINDOW WELLS AND STAIR WELLS 



Aspirator: A fitting or device supplied with water or other fluid under positive pressure that passes through an 
integral orifice or "constriction" causing a vacuum. See Figure 1.2.7 and Section 14.13 



Comment: Backflow prevention is required where the fluid supply is potable water. 






\, 



A - INLET FLUID FLOW 
B - INDUCED VACUUM 
C - COMBINED OUTLET FLOW 



— n b 



Figure 1.2.7 
AN ASPIRATOR FITTING 



16 



2006 National Standard Plumbing Code-Illustrated 



Authority Having Jurisdiction (See also "Adopting Agency") 

The individual official, board, department or agency established and authorized by a state, county, city or other 
political subdivision created by law to administer and enforce the provisions of the plumbing code as adopted or 
amended. 



Automatic Flushing Device: A device that automatically flushes a fixture after each use without the need for 
manual activation. 



Auxiliary Floor Drain: A floor drain that does not receive the discharge from any indirect waste pipe. Auxiliary floor 
drains have no DFU loading. 



Backflow Connection: Any arrangement whereby backflow can occur. 



Comment: See "Cross Connection' 



Backflow (drainage): A reversal of flow in the drainage system. 



Backflow Preventer: A device or means to prevent backflow. See Figures 1.2.5, 1.2.8, 1.2.9, 1.2.23, 
1.2.25, 1.2.26, 1.2.27, 1.2.48, 1.2.66, and 1.2.67. 



Comment: Refer to the definitions of "backflow (water distribution) ", "back-pressure backflow", 
"back-siphonage", "critical level", "cross connection", "double check valve assembly", "reduced 
pressure principle back-pressure backflow preventor", "vacuum breaker, atmospheric", "vacuum 
breaker, pressure type", and "vacuum breaker, spill-proof". 



POTABLE WATER 
TO BUILDING 




CURB VALVE 



Figure 1.2.8 
BACKFLOW CAUSED BY BACK-PRESSURE 



2006 National Standard Plumbing Code-Illustrated 



17 



NOTES: 

1 . Back-pressure backflow is generally caused by water pressure producing equipment within a 
building. 

2. The hot water heating boiler operates at up to 30 psig and has a chemical shot feeder. 

3. The pressure in the public water main can drop below 30 psig due to a shutdown for repair or heavy 
demand forfire fighting operations. 

4. The check valve and pressure reducing valve in the water makeup to the heating system are not 
adequate to prevent back-pressure backflow. 

5. The chemical feeder creates a potential "high hazard" that requires a reduced pressure zone 
backflow preventor (RPZ). Otherwise, a double check valve assembly would be adequate. 

6. An RPZ at Point "A" is required to protect the water distribution system within the building from 
backflow of chemically treated boiler water. 

7. An RPZ at Point "B" would "contain" the building and prevent it from backflowing any potential 
contamination into the public water system. 



Figure 1.2.8 (NOTES) 
BACKFLOW CAUSED BY BACK-PRESSURE 



FLOOD LEVEL RIM 




VACUUM BREAKER NEEDED HERE - 
LOCATED SIX (6 ) INCHES MINIMUM 
ABOVE FLOOD LEVEL RIM 

CHEMICAL SINK FAUCET WITHOUT 
BACKFLOW PREVENTER 



HW 



CW 



POTABLE WATER SUBJECT 
TO BACKFLOW 



Figure 1.2.9 
BACKFLOW CAUSED BY BACK-SIPHONAGE 



Backflow (Water Distribution): The flow of water or other liquids, mixtures or substances from any source or 
sources into the distribution pipes of a potable water system. Back-siphonage is one type of backflow. See 
Figures 1.2.8 and 1.2.9 

Backpressure Backflow: Backflow caused by a higher pressure in the non-potable system than in the potable 
supply system. See Figure 1.2.8 

Back-siphonage: Backflow caused by a greater negative pressure in the potable system than in the non-potable 
supply system. See Figure 1.2.9 



Backwater Valve: A device installed in a drain pipe to prevent backflow. See Figure 1.2.10 



18 



2006 National Standard Plumbing Code-Illustrated 



Comment: Backwater valves are swing-type check valves that are installed in drainage piping to prevent 
the reversal of flow in the piping and overflows due to stoppages, flooding, or other abnormal condi- 
tions. Refer to Section 5.5.1 for where backwater valves are required. 



DIRECTION OF 
DRAINAGE FLOW ■ 




ACCESS COVER 
MECHANICAL SEAL 



^sss: 



SSSS5S55SSSSSSS5SSSSSSS7 



Figure 1.2.10 
A BACKWATER VALVE 

Baptistery: A tank or pool for baptizing by total immersion. 

Bathroom Group: A group of fixtures in a dwelling unit bathroom consisting of one water closet, one or two 
lavatories, and either one bathtub, one combination bath/shower or one shower stall. Other fixtures within the 
bathing facility shall be counted separately when determining the water supply and drainage fixture unit loads. 

Battery of Fixtures: Any group of two or more similar adjacent fixtures that discharge into a common horizontal 
waste or soil branch. See Figure 1.2.11 



Comment: Batteries of fixtures can be "battery vented" in groups of up to eight fixtures in accordance 
with Section 12.13. Fixtures that are "battery vented" do not have to be the same type. 




PLAN VIEW 



Figure 1.2.11 
A BATTERY OF FIXTURES 

Bedpan Steamer: A fixture used for scalding bedpans or urinals by direct application of steam. See Section 
14.10 

Boiler Blow-off: An outlet on a boiler to permit emptying or discharge of sediment. See Figure 1.2.12 



2006 National Standard Plumbing Code-Illustrated 



19 




CONTINUOUS SURFACE BLOWOFF 



BOTTOM 
BLOWOFF VALVES 



y ' /- FLASH STEAM VENT 
r TO OUTDOORS 

I 



VENT 




AIR GAP OR 
AIR BREAK 



TO POINT 

OF DISCHARGE 



Figure 1.2.12 
A BOILER BLOWOFF TANK 



Boiler Blow-off Tank: A vessel designed to receive the discharge from a boiler blow-off outlet and to cool the 
discharge to a temperature that permits its safe discharge to the drainage system. See Figure 1.2.12 



Comment: Boiler blow-off must be cooled to 140°F or less before being discharged into the drainage 
system. If potable water is supplied for cooling, the water source must be protected from backflow. 
An air break can be provided at the discharge from the blow-off tank into the drainage system if the 
makeup water supply to the boiler is protected against backflow. 



Branch: Any part of the piping system other than a riser, main or stack. See Figure 1.2.13 



Comment: Branch piping can serve more than one fixture or appliance. 



20 



2006 National Standard Plumbing Code-Illustrated 




WASTE BRANCH 



STACK 



T 



1 



WATER DISTRIBUTION 
BRANCH 



RISER 



Figure 1.2.13 
BRANCH PIPING 



Branch, Fixture: See "Fixture Branch" 

Branch, Horizontal: See "Horizontal Branch Drain" 

Branch Interval: A distance along a soil or waste stack corresponding, in general, to a story height, but in no 
case less than 8 feet within which the horizontal branches from one floor or story of a building are connected to 
the stack. See Figure 1.2.14 



Comment: Branch intervals are used to determine the potential drainage load on stacks for the purpose 
of sizing the stacks. 



/ 



SOIL OR WASTE STACK 



/~ 



/~ 



8' MINIMUM 



8' MINIMUM 



A-B AND B-D ARE 
BRANCH INTERVALS 
B-C AND C-D ARE 
NOT BRANCH 
INTERVALS 



Figure 1.2.14 
BRANCH INTERVALS 



Branch Vent: See "Vent, Branch" 



2006 National Standard Plumbing Code-Illustrated 



21 



Building: A structure having walls and a roof designed and used for the housing, shelter, enclosure, or support 
of persons, animals, or property. 



Building Classification: The arrangement adopted by the Authority Having Jurisdiction for the designation of 
buildings in classes according to occupancy. See Table 7.21.1 



Comment: The building classifications in Table 7.21.1 for the minimum number of required plumbing 
fixtures include assembly, business, education, factory and industrial, institutional, mercantile, residen- 
tial, storage, and utility/miscellaneous. 



SOIL 
STACK 



SOIL 
STACK 



AREA 
DRAIN 




10 FT MINIMUM 
FROM STORM 
TO SOIL 
CONNECTIONS 



COMBINED 
BUILDING SEWER 



Figure 1.2.15 
A COMBINED BUILDING DRAINAGE SYSTEM 



Building Drain: The lowest piping in a drainage system that receives the discharge from stacks and horizontal 
fixture branches within a building that convey sewage, waste, or other drainage to a building sewer beginning 
three (3) feet outside the building wall. Horizontal fixture branches are sized according to Table 1 1 .5 . 1 B until 
they connect to the building drain or a branch of the building drain that serves two or more horizontal fixture 
branches. See Figure 1.2.16 

Building Drain, Combined: A building drain which conveys both sewage and storm water or other drainage. 
See Figure 1.2.15 



22 



2006 National Standard Plumbing Code-Illustrated 



(7) BUILDING DRAIN - SANITARY 
@ BUILDING DRAIN - STORM 
(5) BUILDING SEWER - SANITARY 
@ BUILDING SEWER- STORM 



END OF BUILDING DRAINS 




- PUBLIC SANITARY SEWER 
PUBLIC STORM SEWER 



Figure 1.2.16 
SEPARATE SANITARY AND STORMWATER BUILDING DRAINS AND SEWERS 

Building Drain, Sanitary: A building drain that conveys sewage only. See Figure 1.2.16 

Building Drain, Storm: A building drain that conveys storm water or other drainage, but no sewage. See 
Figure 1.2.16 

Building Sewer: That part of the drainage system which extends from the end of the building drain and conveys 
its discharge to a public sewer, private sewer, individual sewage-disposal system or other point of disposal. See 
Figure 1.2.16 

Building Sewer, Combined: A building sewer that conveys both sewage and storm water or other drainage. 
See Figure 1.2.15 

Building Sewer, Sanitary: A building sewer that conveys sewage only. See Figure 1.2.16 

Building Sewer, Storm: A building sewer that conveys storm water or other drainage but no sewage. See 
Figure 1.2.16 



2006 National Standard Plumbing Code-Illustrated 



23 



Building Subdrain: That portion of a drainage system that does not drain by gravity into the building sewer or 
building drain. See Figure 1.2.17 



DISCHARGE TO 
GRAVITY DRAIN 



SEWAGE SUMP PIT 
WITH AUTOMATIC c 

SEWAGE PUMP 
OR EJECTOR 



VENT 




BUILDING SUBDRAIN 



Figure 1.2.17 
A BUILDING SUBDRAIN 



Building Trap: A device, fitting, or assembly of fittings, installed in the building drain to prevent circulation of air 
between the drainage system of the building and the building sewer. See Figure 1.2.18 



Comment: Building traps are currently installed only when required by the Authority Having Jurisdic- 
tion. 



6 s1 



VENT NOT LESS THAN 
1/2 THE SIZE 
OF THE BUILDING 
DRAIN 



(Section 5.4) 
CLEANOUTS 



/ 



M« 



BUILDING DRAIN 




FRESH AIR INTAKE 
' (SCREEN COVERED) 



TO BUILDING SEWER 



BUILDING TRAP 



Figure 1.2.18 
A BUILDING TRAP 



24 



2006 National Standard Plumbing Code-Illustrated 



Cesspool: A lined and covered excavation in the ground that receives the discharge of domestic sewage or other 
organic wastes from a drainage system, so designed as to retain the organic matter and solids, but permitting the 
liquids to seep through the bottom and sides. 



Comment: Chapter 16 does not permit cesspools or cesspits, into which untreated sewage is discharged 
and allowed to seep into the ground. Chapter 16 requires septic tanks to retain the sewage until digested 
and absorption trenches or seepage pits for underground disposal of the effluent. 



Chemical Waste: See "Special Wastes" See Sections 2.10 and 9.4 
Circuit Vent: See "Vent, Circuit" See Figure 12.13.1 

Clear Water Waste: Effluent in which impurity levels are less than concentrations considered harmful by the 
Authonty Having Jurisdiction, such as cooling water and condensate drainage from refrigeration and air condition- 
ing equipment, cooled condensate from steam heating systems, and residual water from ice making processes 



Comment: Refer to Section 9.1.8 for whether a clear water waste requires an air gap or an air break at 
its discharge into the drainage system. 



Clinical Sink: A sink designed primarily to receive wastes from bedpans, having a flushing rim, intergral trap 
with a visible trap seal, and having the same flushing and cleansing characteristics as a water closet. See Sec- 



tion 14.8 



Code: These regulations, or any emergency rule or regulation that the Authority Having Jurisdiction may lawfully 



Combination Fixture: A fixture combining one sink and laundry tray, or a two- or three-compartment sink 
laundry tray in one unit. See Figure 1.2.19 



or 



Comment: Combination fixtures with waste outlets not more than 30 inches apart can have one trap 



THREE COMPARTMENT SINK 



~-Ef 



~-Ef 



1 1 

i 



^ 



=EF 



SINK AND LAUNDRY TRAY 



I I. 



^ 



Figure 1.2.19 
COMBINATION FIXTURES 

Combination Thermostatic/Pressure Balancing Valve: See "Thermostatic/Pressure Balancing Valve 
Combined" ' 



wet 



Combination Waste and Vent System: A designed system of waste piping embodying the horizontal „„, 
venting of one or more sinks or floor drains by means of a common waste and vent pipe adequately sized to 
provide free movement of air above the flow line of the drain. See Figure 1.2.20 and Section 12 17 



2006 National Standard Plumbing Code-Illustrated 



25 



Comment #1: Combination waste and vent piping systems are permitted where conditions preclude the 
installation of a conventionally vented system. Such systems are frequently used in exhibition halls and 
other spaces where long clear spans are required without partitions or pipe chases. 

Comment #2: Only floor drains, floor receptors, sinks, lavatories, and standpipes can be discharged into 
a combination waste and vent piping system. 




TO CONNECTION WITH 
CONVENTIONALLY SIZED 
AND VENTED DRAINAGE 
PIPING 



OVERSIZED COMBINATION WASTE & VENT 
PIPING PER TABLE 12.17.4 



Figure 1.2.20 
COMBINATION WASTE AND VENT PIPING 



Combined Building Drain: See "Building Drain, Combined" 
Combined Building Sewer: See "Building Sewer, Combined" 
Common Vent: See "Vent, Common" 

Conductor: A pipe within a building that conveys stormwater from a roof to its connection to a building storm 
drain or other point of disposal. See Figure 1.2.21 



Comment: A vertical stormwater drainpipe on the exterior of a building is a leader. 



ROOF DRAIN 



LtTl 




TO AN APPROVED 
POINT OF DISCHARGE 



Figure 1.2.21 
A STORMWATER CONDUCTOR 



26 



2005 National Standard Plumbing Code-Illustrated 



Contamination: The impairment of the quality of the potable water that creates an actual hazard to the public health 
through poisoning or through the spread of disease by sewage, industrial fluids or waste. (See the definition of 
"pollution"). 



Continuous Vent: See "Vent, Continuous" 

Continuous Waste: A drain from two or more fixtures connected to a single trap. See Figure 1.2.22 



Comment: Continuous waste piping can connect up to three adjacent sinks or lavatories to a single trap 
if the fixture outlets are no more than 30" apart. See Section 5.1. 



EZUt 




J 



TRAP 



END OUTLET 






3T 



TRAP 
CENTER OUTLET 



Figure 1.2.22 
CONTINUOUS WASTE PIPING 



Critical Level: The marking on a backflow prevention device or vacuum breaker established by the manufac- 
turer, and usually stamped on the device by the manufacturer, that determines the minimum elevation above the 
flood level rim of the fixture or receptor served at which the device must be installed. When a backflow preven- 
tion device does not bear a critical level marking, the bottom of the vacuum breaker, combination valve, or the 
bottom of any approved device constitutes the critical level. See Figure 1.2.23 and Sections 10.5.5.1), c, and e 



VACUUM BREAKER 




POTABLE 
WATER 



REQUIRED DISTANCE 
(See Section 10.5.5) 



OVERFLOW OR 
FLOOD LEVEL 



FIXTURE, 

APPLIANCE, OR 

RECEPTOR 



Figure 1.2.23 
THE CRITICAL LEVEL (C-L) OF A VACUUM BREAKER 



2006 National Standard Plumbing Code-Illustrated 



27 



Cross Connection: Any connection or arrangement between two otherwise separate piping systems, one of that 
contains potable water and the other either water of questionable safety, steam, gas, or chemical, whereby there 
may be a flow from one system to the other, the direction of flow depending on the pressure differential between 
the two systems (See "Backflow and Back-Siphonage). See Figures 1.2.8 and 1.2.9 



Comment: The backflow of contamination into a potable water system through a cross connection can 
occur by back-siphonage caused by the water system or back-pressure from the source of contamination. 



Day Care Center: A facility for the care and/or education of children ranging from 2-1/2 years of age to 5 years 
of age. 

Day Nursery: A facility for the care of children less than 2-1/2 years of age. 

Dead End, Potable Water: A branch line terminating at a developed length of two (2) feet or more from 
an active potable water line by means of a plug or cap. See Figure 1.2.24 



Comment: An extension of 2 feet or more to make a cleanout accessible is not considered to be a dead 
end. 



VENT i— - 



-=k 



DEAD END 



GREATER THAN 2 FEET 



\ 



DRAIN h 



1 



y 



DEAD END 



GREATER THAN 2 FEET 



Figure 1.2.24 
DEAD ENDS IN DRAIN AND VENT PIPING 



Dead End, Soil, Waste, or Vent: A branch leading from a soil, waste or vent pipe, building drain, or 
building sewer line and terminating at a developed length of two (2) feet or more by means of a plug, cap, 
or other closed fitting. 

Developed Length: The length of a pipe line measured along the center line of the pipe and fittings. 

Diameter: See "Size of Pipe & Tubing" 

Domestic Sewage: The water-borne wastes derived from ordinary living processes. 



28 



2006 National Standard Plumbing Code-Illustrated 



OPTIONAL 
WYE STRAINER 



POTABLE 

WATER 

SUPPLY 



c t 




TEST PORTS 



RESILIENT SEATED 
GATE VALVES 



— v*— - 



TO BACKPRESSURE OR BACKSIPHONAGE 
NON-HEALTH HAZARD APPLICATIONS 



Figure 1.2.25 
A DOUBLE CHECK VALVE ASSEMBLY 



Double Check Valve Assembly: A backflow prevention device consisting of two independently acting check 
valves, internally force loaded to a normally closed position between two tightly closing shut-off valves, and with 
means of testing for tightness. See Figure 1.2.25 

Double Offset: See "Offset, Double" 

Downspout: See "Leader" 

Drain: Any pipe that carries waste or water-borne wastes in a building drainage system. 

Drainage Pipe: See "Drainage System" 

Drainage, Sump : A liquid and air-tight tank that receives sewage and/or liquid waste, located below the 
elevation of a gravity drainage system, that is emptied by pumping. 

Drainage System: All the piping within public or private premises that conveys sewage, rain water, or other 
liquid wastes to a point of disposal. It does not include the mains of a public sewer system or private or public 
sewage-treatment facilities. 

Drainage System, Building Gravity: A drainage system that drains by gravity into the building sewer. See 
Figure 1.2.16 

Drainage System, Sub-building: See "Building Subdrain" See Figure 1.2.17 

Dry Vent: See "Vent, Dry" 

Dry Well: See "Leaching Well" 

Dual Vent: See "Vent, Common" 

Dwelling Unit, Multiple: A room, or group of rooms, forming a single habitable unit with facilities that are used, 
or intended to be used, for living, sleeping, cooking and eating; and whose sewer connections and water supply, 
within its own premise, are shared with one or more other dwelling units. Multiple dwelling units include guest 
rooms in hotels and motels. 



2006 National Standard Plumbing Code-Illustrated 



29 



Comment: Apartments, condominiums, and guest rooms in hotels and motels are examples of multiple 
dwelling units. 



Dwelling Unit, Single: A room, or group of rooms, forming a single habitable unit with facilities that are used, or 
intended to be used, for living, sleeping, cooking and eating; and whose sewer connections and water supply are, 
within its own premise, separate from and completely independent of any other dwelling. 

DWV: An acronym for "drain-waste-vent" referring to the combined sanitary drainage and venting systems. 
This term is equivalent to "soil-waste-vent" (SWV). 



Effective Opening: The minimum cross-sectional area at the point of water supply discharge, measured or 
expressed in terms of (1) diameter of a circle, or (2) if the opening is not circular, the diameter of a circle of 
equivalent cross-sectional area. See Figures 1.2.26 and 1.2.27 



Comment: The required air gap distance for a water supply outlet is based on its effective opening. The 
air gap must be increased if the outlet is near a wall or other vertical surface. Refer to Table 10.5.2 for 
minimum air gaps for plumbing fixtures. 




AIR GAP NOT LESS 
THAN 2 X "D" 



EFFECTIVE OPENING (DIAMETER "D") 



Figure 1.2.26 
THE EFFECTIVE OPENING OF A POTABLE WATER OUTLET 



POTABLE 
WATER - 
SUPPLY 



PUMP 

SUCTION 

TANK 



FLOAT 
VALVE 



PUMP DISCHARGE TO A 
NON-POTABLE WATER SYSTEM 



p AIR GAP 
^ J_(See Table 10.5.2) 




D- EFFECTIVE OPENING OF WATER SUPPLY OUTLET 



PUMP 



TT ^ TTr _ <rrr ™. „^,,, t ._,_. tr ,, TT v , v vv x y% y TTX , i^^ KKK yy^ K \ ^.^ 



Figure 1.2.27 
AiN AIR GAP BETWEEN POTABLE AND NON-POTABLE WATER SYSTEMS 

Equivalent Length: The length of straight pipe of a specific diameter that would produce the same frictional 
resistances as a particular fitting or line comprised of pipe and fittings. See Tables B.9.7A and B.9.7B 

Existing Plumbing System: An existing plumbing system, or any part thereof, installed prior to the effective 
date of this Code. 

Existing Work: A plumbing system, or any part thereof, installed prior to the effective date of this Code. 



30 



2006 National Standard Plumbing Code-Illustrated 



Family: One or more individuals living together and sharing the same facilities. 
Fixture: See "Plumbing Fixture" 

Fixture Branch, Drainage: A drain serving one or more fixtures that discharges into another drain See 
Figure 1.2.28 



Comment: See Table 11. 5. LB for the maximum number of drainage fixture units (DFV) permitted on 
each size of horizontal fixture branch. 



VENT 
T 



VENT 

y 



2 






n 



t^ 



FIXTURE BRANCH 



FIXTURE DRAINS 



Figure 1.2.28 
A FIXTURE DRAIN AND FIXTURE BRANCH 



Fixture Branch, Supply: A branch of the water distribution system supplying one fixture. See Figure 1.2.29 



Comment: See Table 10.14.2.Afor minimum supply fixture branch sizes for various fixtures. 




I^C 



FIXTURE SUPPLY 
BRANCH 



Figure 1.2.29 
A FIXTURE SUPPLY BRANCH AND FIXTURE SUPPLY TUBE 

Fixture Drain: The drain from the trap of a fixture to the junction of that drain with any other drain pipe. 



2006 National Standard Plumbing Code-Illustrated 



31 



Fixture Unit (Drainage -DFU): An index number that represents the load of a fixture on the drainage system 
so that the load of various fixtures in various applications can be combined. The value is based on the volume or 
volume rate of drainage discharge from the fixture, the time duration of that discharge, and the average time 
between successive uses of the fixture. One DFU was originally equated to a drainage flow rate of one cubic foot 
per minute or 7.5 gallons per minute through the fixture outlet. See Table 11.4.1 

Fixture Unit (Water Supply - WSFU): An index number that represents the load of a fixture on the water 
supply system so that the load of various fixtures in various applications can be combined. The value is based on 
the volume rate of supply for the fixture, the time duration of a single supply operation, and the average time 
between successive uses of the fixture. Water supply fixture units were originally based on a comparison to a 
flushometer valve water closet, which was arbitrarily assigned a value of 10 WSFU. See Table 10.14.2A. Also 
Tables B.5.2 and B.5.3. 

Flexible Water Connector: A connector under continuous pressure in an accessible location that connects a supply 
fitting, faucet, dishwasher, cloths washer, water heater, water treatment unit, or other fixture or equipment to a stop 
valve or its water supply branch pipe 



Flood Level: See "Flood Level Rim" 

Flood Level Rim: The edge of the receptor or fixture over which water flows if the fixture is flooded. See 
Figure 1.2.30 



Comment: Air gaps are measured from above the flood level rim of receptors and fixtures. 



FLOOD LEVEL RIM 



FLOOD LEVEL RIM 




WATER 
CLOSET 



URINAL 



FLOOR 
DRAIN 



SINK 



LAVATORY 



BATHTUB 



Figure 1.2.30 
THE FLOOD LEVEL RIM OF FIXTURES 



Flooded: The condition that results when the liquid in a receptor or fixture rises to the flood level rim. 

Flow Pressure: The pressure in the water supply pipe near the faucet or water outlet while the faucet or water 
outlet is fully open and flowing. See Figure 1.2.31 



Comment: The minimum required flowing water pressure for most fixtures and appliances is 15 psig. 
Blowout water closets and blowout urinals require 25 psig minimum. Some one-piece water closets 
require 30 psig minimum and 1/2" supply tubes. 



32 



2006 National Standard Plumbing Code-Illustrated 



FLOW PRESSURE 

NO FLOW PRESSURE 




Figure 1.2.31 
THE FLOW PRESSURE OF THE WATER SUPPLY TO AN OUTLET 



Flush Pipes and Fittings: The pipe and fittings that connect a flushometer valve or elevated flush tank to a water 
closet, urinal, or bed pan washer. 

Flushing Type Floor Drain: A floor drain that is equipped with an integral water supply connection, enabling 
flushing of the drain receptor and trap. See Figure 1.2.32 



Comment: The water supply to flushing floor drains must be protected from hackflow. 




DRAIN 



TRAP FLUSHING CONNECTION SUPPLIED FROM 
AN APPROPIATE BACKFLOW PREVENTION DEVICE 



Figure 1.2.32 
A FLUSHING TYPE FLOOR DRAIN 

Flush Valve: A device located at the bottom of a tank for flushing water closets and similar fixtures. See 
Figure 1.2.33 



2006 National Standard Plumbing Code-Illustrated 



33 



OVERFLOW 
TUBE -^ 



jT 




LOWER LIFT WIRE 



TANK SEAL BALL 



FLUSH VALVE ASSEMBLY 



Figure 1.2.33 

A FLUSH VALVE IN A WATER CLOSET FLUSH TANK 



Flushometer Tank: A water closet flush tank that uses an air accumulator vessel to discharge a predetermined 
quantity of water into the closet bowl for flushing purposes. See Figure 1.2.34 



Comment: Flushometer tanks are pressure-assisted flush tanks that store water for flushing water closets 
at the inlet water supply pressure, as opposed to gravity tanks. The discharge rate from flushometer 
tanks is approximately 35 gallons per minute. 



PRESSURE TANK 




Figure 1.2.34 
A PRESSURE-ASSISTED WATER CLOSET WITH A FLUSHOMETER TANK 



Flushometer Valve: A device that discharges a predetermined quantity of water to fixtures for flushing and is 
closed by direct water pressure or other means. See Figure 1.2.35 



Comment: Flushometer valves are typically used on public water closets and public urinals. They can 
be manually operated or electronically operated. 



34 



2006 National Standard Plumbing Code-Illustrated 






Figure 1.2.35 
A FLUSHOMETER VALVE 

Force Main: A main that delivers waste water under pressure from a sewage ejector or pump to its destina- 
tion. 

Full-way valve: Full-way valves include gate valves, full port ball valves, and other valves that are identified by their 
manufacturer as full port or full bore. 

Grade: The fall (slope) of a line of pipe in reference to a horizontal plane. See Figure 1.2.36. 



Comment: See Tables 11.5.1 A and 11.5.1Bfor sizing building drains, building sewers, and horizontal 
fixture branches. See Table 13.6.2 for stormwater drains. 



SLOPING GRAVITY DRAIN 




FLOW 



FALL 



Figure 1.2.36 
GRADE ON A SLOPING GRAVITY DRAIN 

Grease Interceptor: A plumbing appurtenance that is installed in the sanitary drainage system to intercept oily and 
greasy wastes from wastewater discharges, typically in commercial kitchens and food processing plants. Such 
equipment has the ability to intercept commonly occurring free-floating fats and oils. 

Grease Recovery Device (GRD): A plumbing appurtenance that is installed in the sanitary drainage system to 
intercept and remove free-floating fats, oils, and grease from wastewater discharges, typically in commercial kitchens 
and food processing plants. Such equipment operates on a time or event- controlled basis and has the ability to remove 
the entire range of commonly occurring free-floating fats, oils, and grease automatically without intervention from the 
user except for maintenance. The removed material is essentially water-free, which allows for recycling of the 
removed product. 

Grease Trap: See "Interceptor" 



2006 National Standard Plumbing Code-Illustrated 



35 



Grinder Pump: A pump for sewage that shreds or grinds the solids in the sewage that it pumps. 

Ground Water: Subsurface water occupying the zone of saturation, (a) confined ground water - a body of ground 
water overlaid by material sufficiently impervious to sever free hydraulic connection with overlying ground water, (b) 
free ground water - ground water in the zone of saturation extending down to the first impervious barrier. 

Half-Bath: A room that contains one water closet and one lavatory within a dwelling unit. 

Hangers: See "Supports" See Chapter 8 

Health Hazard In backfiow prevention, an actual or potential threat of contamination of the potable water supply 
to the plumbing system of a physical or toxic nature that would be a danger to health. Health hazards include any 
contamination that could cause death, illness, or spread of disease. 

Horizontal Branch Drain: A drain pipe extending laterally from a soil stack, waste stack or building drain with 
or without vertical sections or branches, that receives the waste discharged from one or more fixture drains and 
conducts the waste to a soil stack, waste stack, or building drain. 

Horizontal Pipe: Any pipe or fitting that makes an angle of less than 45° with the horizontal. See Figure 
1.2.37 



Comment: The sizing of offsets in drainage stacks varies depending on whether the offset is horizontal or 
vertical. See Section 11.6. 



HORIZONTAL PIPE 
(LESS THAN 45°) 




HORIZONTAL / \ HORIZONTAL PLANE 



Figure 1.2.37 
THE DEFINITION OF "HORIZONTAL PIPE" 

Hot Water: Potable water that is heated to a required temperature for its intended use. 

House Drain: See "Building Drain" 

House Sewer: See "Building Sewer" 

House Trap: See "Building Trap" 

Indirect Connection (Waste): The introduction of waste into the drainage system by means of an air gap or air 
break. 

Indirect Waste Pipe: A waste pipe that does not connect directly with the drainage system, but which dis- 
charges into the drainage system through an air break or air gap into a trap, fixture, receptor or interceptor. See 
Figure 1.2.38 



36 2006 National Standard Plumbing Code-Illustrated 



INDIRECT WASTE PIPE 

AIR BREAK OR AIR GAP 
(Section 9.1) 




—WALK IN REFRIGERATOR 
SINK 



^^ 



r 

AIR BREAK OR 
AIR GAP 
(Section 9.1) 



& 




INDIRECT WASTE PIPE 



INDIRECT WASTE 
RECEPTORS 



Figure 1.2.38 
INDIRECT WASTE PIPES 



Individual Vent: See "Vent, Individual' 



Industrial Wastes: Liquid or liquid-borne wastes resulting from the processes employed in industrial and 
commercial establishments. 



Comment: Industrial wastes must not be discharged into public sewers if they will damage the sewer or 
interfere with the operation of the sewage treatment plant. 



Insanitary: Contrary to sanitary principles -- injurious to health. 
Installed: Altered, changed or a new installation . 

Interceptor: A device designed and installed so as to separate and retain deleterious, hazardous, or undesirable 
matter from normal wastes while permitting norma! sewage or liquid wastes to discharge into the drainage system 
by gravity. See Figure 1.2.39 



Comment: Interceptors include grease interceptors, oil/water separators, sand interceptors, solids 
interceptors, and neutralizing or dilution tanks. 




-. ... _ 



STATIC WATER LINE 



TRAP SEAL 



I 1 1 




~ 



Figure 1.2.39 
AN INTERCEPTOR 



2006 National Standard Plumbing Code-Illustrated 



37 



Invert: The lowest portion of the inside of a horizontal pipe. See Figure 1.2.40 



Comment: Invert elevations are used to design and install drainage piping at the required grade or 
slope. 




INVERT 



HORIZONTAL PIPE 



Figure 1.2.40 
THE INVERT OF A DRAIN PIPE 

Leaching Well or Pit: A pit or receptor having porous walls that permit the liquid contents to seep into the ground. 
See Figure 1.2.41 



Comment: Leeching wells or pits are used to disperse the effluent from septic tanks into the ground for 
secondary treatment. They may supplement or be used in lieu of absorption trenches. Leaching wells or 
pits can only be used where there is very deep soil of good permeability and considerable depth to 
groundwater. 



38 



2006 National Standard Plumbing Code-Illustrated 



COVER 



CONC. TOP -, \ 



FROM SEPTIC TANK — i, [Jl 



CORBEL 1/3 WIDTH 
OF BLOCK 
MORTAR IN JOINTS 



BLOCKS MAY BE LAYERED 
WITHOUT MORTAR IN JOINTS 

PLACE BLOCK CELLS IN 
HORIZONTAL POSITION 
EVERY OTHER COURSE 

FILL 3" ANNULAR SPACE 
WITH CLEAN COURSE 
GRAVEL OR CRUSED STONE- 



PIT WALL 




SECTION 



SMALL AMOUNT OF MORTAR v « iX 

BETWEEN BLOCKS ADDS 

RIGIDITY 



BUTT BLOCKS FOR 
RADIAL ARCH SUPPORT 




Figure 1.2.41 
A LEACHING OR SEEPAGE WELL OR PIT 

Leader: An exterior vertical drainage pipe for conveying storm water from roof or gutter drains. See Figure 
1.2.42 



Comment: A stormwater drainpipe on the interior of a building is a conductor. 



I? 



LEADER 



&- 



I 



SPLASH BLOCK OR OTHER 
APPROVED POINT OF DISPOSAL 



Figure 1.2.42 
A STORMWATER LEADER 



2006 National Standard Plumbing Code-Illustrated 



39 



Load Factor: The percentage of the total connected fixture unit flow which is likely to occur at any point in the 
drainage system. 

Local Ventilating Pipe: A pipe on the fixture side of the trap through which vapor or foul air is removed from a 
fixture. See Figure 1.2.43 



Comment: Local vent piping may be required for clinical sinks, bedpan washers, and sterilizers. Local 
vents for sterilizers must not be connected to local vents for clinical sinks and bedpan washers. Refer to 
Section 14.9 for clinical sinks and bedpan washers. Refer to Section 14.10 for sterilizers. 



TO OUTDOORS 

2zfe 



LOCAL VENT — — 



STERILIZER 



□ 



' ' 



Figure 1.2.43 
A STERILIZER LOCAL VENTILATING PIPE 

Loop Vent: See "Vent, Loop" 

Low Hazard: See "Hazard, Low" 

Macerating Toilet System: A system that collects drainage from a single water closet, lavatory and/or bathtub 
located in the same room. It consists of a receiving container, agrinderpump, and associated level controls. The system 
pumps shredded or macerated sewage up to a point of discharge 

Main: The principal pipe artery to which branches may be connected. 

Main Sewer: See "Public Sewer" 

May: The word "may" is a permissive term. 

Medical Gas System: The complete system used to convey medical gases for direct application from central 
supply systems (bulk tanks, manifolds and medical air compressors) through piping networks with pressure and 
operating controls, alarm warning systems, etc., and extending to station outlet valves at use points. 



Comment: Medical gas systems must comply with NFPA 99 - Standard for Health Care Facilities or 
NFPA 99C - Gas and Vacuum Systems. NFPA 99 is the parent document for NFPA 99C. NFPA 99 
addresses all safety aspects of health care facilities, whereas NFPA 99C limits itself to the medical gas 
and vacuum portions of NFPA 99. 



Medical Vacuum Systems: A system consisting of central-vacuum-producing equipment with pressure and 
operating controls, shut-off valves, alarm warning systems, gauges and a network of piping extending to and 
terminating with suitable station inlets to locations where suction may be required. 



40 



2006 National Standard Plumbing Code-Illustrated 



Comment: Refer to the comment under Medical Gas System. 



Multiple Dwelling: A building containing two or more dwelling units. 

Non-Health Hazard: In backflow prevention, an actual or potential threat to the physical properties or potability 
of the water supply to the plumbing system, but which would not constitute a health or system hazard. 

Non-potable Water: Water not safe for drinking or for personal or culinary use. 

Nominal Size: A standard expression in inches and fractions thereof to denote equal. Existing in name only and 
not in actuality. 

Nuisance: Public nuisance at common law or in equity jurisprudence; whatever is dangerous to human life or 
detrimental to health; whatever building, structure, or premises is not sufficiently ventilated, sewered, drained, 
cleaned, or lighted in reference to its intended or actual use; and whatever renders the air, human food, drink or 
water supply unwholesome. 



Offset: A combination of elbows or bends that brings one section of the pipe out of line but into a line parallel 
with the other section. See Figure 1.2.44 - Parts A and B for single offsets 



Comment: Offsets can occur in vertical and horizontal piping. Offsets can consist of90-degree, 45- 
degree, or other angle fittings. Single offsets have one change of alignment. 



K~\ 



4 — \ 



\ 



Figure 1.2.44 
OFFSETS IN PIPING 

Offset, Double: Two offsets installed in succession or series in a continuous pipe. See Figure 1.2.44 - Parts 
E and F 



Comment: Double offsets have two offsets, both away from the original alignment of the pipe. 



Offset, Return: A double offset installed so as to return the pipe to its original alignment. See Figure 1.2.44 
Parts C and D 



Comment: Return offsets have two offsets, both in different directions. The second offset does not 
necessarily bring the pipeline back into exact alignment with the first. The alignment of the piping on 
both sides of the offset is not necessarily exactly the same laterally. 



Oil Interceptor: See "Interceptor" 

Person: A natural person, his heirs, executors, administrators or assigns; including a firm, partnership or corpora- 
tion, its or their successors or assigns. Singular includes plural; male includes female. 



2006 National Standard Plumbing Code-Illustrated 



41 



Pitch: See "Grade" 

Plenum: An enclosed portion of the building structure, other than an occupiable space being conditioned, that is 
designed to allow air movement, and thereby serve as part of an air distribution system. 

Plumbing 

The practice, materials, and fixtures within or adjacent to any building structure or conveyance, used in the 
installation, maintenance, extension, alteration and removal of any piping, plumbing fixtures, plumbing appliances, 
and plumbing appurtenances in connection with any of the following: 

a.. Sanitary drainage system and its related vent system, 

b. Storm water drainage facilities, 

c . Public or private potable water supply systems, 

d. The initial connection to a potable water supply upstream of any required backflow prevention 
devices and the final connection that discharges indirectly into a public or private disposal system, 

e. Medical gas and medical vacuum systems, 

f . Indirect waste piping including refrigeration and air conditioning drainage, 

g. Liquid waste or sewage, and water supply, of any premises to their connection with an approved 
water supply system or to an acceptable disposal facility. 

NOTE: The following are excluded from the definition: 

1 . All piping, equipment or material used exclusively for environmental control. 

2. Piping used for the incorporation of liquids or gases into any product or process for use in the 
manufacturing or storage of any product, including product development. 

3 . Piping used for the installation, alteration, repair or removal of automatic sprinkler systems 
installed for fire protection only. 

4. The related appurtenances or standpipes connected to automatic sprinkler systems or overhead or 
underground fire lines beginning at a point where water is used exclusively for fire protection. 

5. Piping used for lawn sprinkler systems downstream from backflow prevention devices. 

Plumbing Appliance: Any one of a special class of plumbing fixture that is intended to perform a special 
plumbing function. Its operation and/or control may be dependent upon one or more energized components, such 
as motors, controls, heating elements, or pressure or temperature-sensing elements. Such fixtures may operate 
automatically through one or more of the following actions: a time cycle, a temperature range, a pressure range, a 
measured volume or weight; or the fixture may be manually adjusted or controlled by the user or operator. 



Comment: Plumbing appliances include clothes washers, dishwashers, food-waste-disposal and grinder 
units, water heaters, water softeners, and similar devices. Refer to Table 3.1.3 - Part VII for listed 
appliances. 



Plumbing Appurtenance: A manufactured device, a prefabricated assembly, or an on-the-job assembly of 
component parts, that is an adjunct to the basic piping system and plumbing fixtures. An appurtenance demands 
no additional water supply, nor does it add any discharge load to a fixture or to the drainage system. It is pre- 
sumed that an appurtenance performs some useful function in the operation, maintenance, servicing, economy, or 
safety of the plumbing system. 



Comment: Some examples of plumbing appurtenances are water filters, backflow prevention devices, 
backwater valves, interceptors, separators, and neutralizing or dilution tanks. Refer to Table 3.1.3 - Part 
VIII for listed appurtenances. Plumbing appurtenances do not change the load on the water supply or 
drainage system. 



42 



2006 National Standard Plumbing Code-Illustrated 



Plumbing Fixture: A receptacle or device connected to the water distribution system of the premises, and 
demands a supply of water there from; or discharges used water, liquid-borne waste materials, or sewage either 
directly or indirectly to the drainage system of the premises; or which requires both a water supply connection and 
a discharge to the drainage system of the premises. Plumbing appliances as a special class of fixture are further 
defined. 



Comment: Plumbing fixtures include water closets, urinals, bidets, lavatories, bathtubs, whirlpool baths, 
showers, sinks, floor drains, and receptors. Refer to Table 3.1.3 - Part Vfor listed plumbing fixtures. 



Plumbing Inspector: See "Authority Having Jurisdiction" 

Plumbing System: Includes the water supply and distribution pipes, plumbing fixtures and traps; soil, waste and 
vent pipes; sanitaiy and storm drains and building sewers; including their respective connections, devices and 
appurtenances to an approved point of disposal. 

Pollution "Potable Water": An impairment of the quality of the potable water to a degree that does not create 
a hazard to the public health but that does adversely and unreasonably affect the aesthetic qualities of such 
potable water for domestic use. (See the definition of "contamination"). 

Pool: See "Swimming Pool" 

Potable Water: Water free from impurities present in amounts sufficient to cause disease or harmful physiologi- 
cal effects and conforming in its bacteriological and chemical quality to the requirements of the Public Health 
Service Drinking Water Standards or the regulations of the public health authority having jurisdiction. 

Powder Room: See "Half-Bath" 

Pressure Assisted Water Closet: See "Water Closet, Pressure Assisted" 

Pressure Balancing Valve: A mixing valve which senses incoming hot and cold water pressures and compen- 
sates for fluctuations in either to stabilize its outlet temperature. 



Comment: Pressure balancing control valves for individual bathing facilities must comply with ANSI/ 
ASSE 1016, Type P. 



Private Sewage Disposal System: A system for disposal of domestic sewage by means of a septic tank or 
mechanical treatment, designed for use apart from a public sewer to serve a single establishment or building. See 
Chapter 16 

Private Sewer: A sewer not directly controlled by public authority. 



Comment: A private sewer connects a building to a private sewage disposal system. 



Private Use, Public Use: 

Private Use - Plumbing facilities for the private and restricted use of one or more individuals in dwelling units 
(including hotel and motel guest rooms), and other plumbing facilities that are not intended for public use. Refer to 
the definition of "Public Use". 



2006 National Standard Plumbing Code-Illustrated 43 



Public Use - Plumbing facilities intended for the unrestricted use of more than one individual (including employ- 
ees) in assembly occupancies, business occupancies, public buildings, transportation facilities, schools and other 
educational facilities, office buildings, restaurants, bars, other food service facilities, mercantile facilities, manufac- 
turing facilities, military facilities, and other plumbing installations that are not intended for private use. Refer to 
the definition of "Private Use". 

Private Water Supply: A supply, other than an approved public water supply, which serves one or more build- 
ings. See Figure 1.2.46 and Chapter 17 



WELL SEAL 
(Section 17.9.1) 



PRESSURE TANK 
(Section 17.2.4 .A) 



PITLESS ADAPTER 



WELL CASING- 




TO POINT OF USE 



TANK DRAIN 
(Section 17.5.5) 



SUBMERSIBLE PUMP 
(Section 17.6) 

WELL 



UZJ 



Figure 1.2.46 
A TYPICAL PRIVATE WATER SUPPLY SYSTEM 



Public Sewer: A common sewer directly controlled by public authority. 



Comment: This Code does not cover public sewers. The design and construction of public sewers is 
regulated by the sewage authority, a public works department, or other Authority Having Jurisdiction. 



Public Toilet Room: A toilet room intended to serve the transient public, such as in, but not limited to the 
following examples: service stations, train stations, airports, restaurants, and convention halls. 

Public Water Main: A water supply pipe for public use controlled by public authority. 



Comment: This Code does not cover public water mains. The design and construction of public water 
mains is regulated by the water purveyor, a public works department, or other Authority Having Juris- 
diction. 



Pump Assisted Water Closet: See "Water Closet, Pump Assisted" 

Receptor: A fixture or device which receives the discharge from indirect waste pipes. See Figure 1.2.47 



Comment: Receptors include floor drains, standpipes, and certain sinks. 



44 



2006 National Standard Plumbing Code-Illustrated 



OPEN TOP OR 

FULL / PARTIAL TOP GRATE 




FLOOR SINK 



Figure 1.2.47 
AN INDIRECT WASTE RECEPTOR 



Reduced Pressure Backflow Preventer Assembly: See Reduced Pressure Zone Backflow Preventer 
Assembly 

Reduced Pressure Principle Assembly: A reduced pressure zone backflow preventer assembly. 

Reduced Pressure Zone Backflow Preventer Assembly: A backflow prevention device consisting of two 
independently acting check valves, internally force loaded to a normally closed position and separated by an 
intermediate chamber (or zone), in which there is an automatic relief means of venting to atmosphere internally 
loaded to a normally open position, and with means for testing for tightness of the checks and opening of the relief 
means. See Figure 1.2.48 



Comment: Reduced pressure principle backflow preventor assemblies provide the highest level of 
protection against backpressure backflow. The shutoff valves on these assemblies are resiliency seated 
to assure tight close-off for testing. Provisions must be made to drain any discharge from the relief vent 
outlet, which may occur due to normal variations in system pressure. 



SHUT-OFF 
VALVE 



FLOW- 




FLOW- 



VENT OUTLET 



Figure 1.2.48 
A REDUCED PRESSURE BACKFLOW PREVENTER ASSEMBLY 



Relief Vent: See "Vent, Relief 
Return Offset: See "Offset, Return" 
Revent Pipe: See "Vent, Individual" 



2006 National Standard Plumbing Code-Illustrated 



45 



Rim: An unobstructed open edge of a fixture. See Figure 1.2.30 



Comment: The flood level rim of a fixture or appliance is the level from which it will overflow if its drain 
outlet is closed or blocked. 



Riser: A water supply pipe that extends vertically one full story or more to convey water to branches or to a 
group of fixtures. See Figure 1.2.49 



Comment: The term "riser" refers to vertical water supply piping serving one or more fixtures in 
buildings having one or more story heights. 



WATER SUPPLY 
RISER- 



^ 



I 



TO FIXTURES 



TO FIXTURES 



TO FIXTURES 



- RISER SHUT OFF VALVE 



Figure 1.2.49 
A WATER SUPPLY RISER 



Roof Drain: A drain installed to receive water collecting on the surface of a roof and to discharge it into a leader 
or a conductor. See Figure 1.2.50 



Comment: Roof drains include flat deck drains and scupper drains. 




Figure 1.2.50 
A GENERAL PURPOSE ROOF DRAIN 

Roughing-in: The installation of all parts of the plumbing system that can be completed prior to the installation of 
fixtures. This includes drainage, water supply, and vent piping, and the necessary fixture supports, or any fixtures 
that are built into the structure. 



46 



2006 National Standard Plumbing Code-Illustrated 



Safe Waste: See "Indirect Waste Pipe" 

Sand Filter: A treatment device or structure, constructed above or below the surface of the ground, for removing 
solid or colloidal material of a type that cannot be removed by sedimentation, from septic tank effluent See 
Figure 1.2.51 and Section 16.12 



Comment #1: Sand filters provide additional treatment of septic tank effluent. They are used where the 
soil depth is shallow and cannot provide sufficient secondary treatment of the effluent. 



Comment #2: Sand interceptors (or sand traps) are associated with oil/water separators in Chapter 6. 




REMOVABLE COVER 



SETTLING BEDS 



Figure 1.2.51 
A SAND FILTER FOR SEPTIC TANK EFFLUENT 



Sand Interceptor: See "Interceptor" See Section 6.4 



Comment: Sand interceptors (or sand traps) are associated with oil/water separators in Chapter 6. Sand 
filters are associated with the effluent from septic tanks in Chapter 16. 



Sand Trap: See "Interceptor" 



Comment: The term "sand trap " is used interchangeably with "sand interceptor. " 



Sanitary Sewer: A sewer that carries sewage and excludes storm, surface and ground water. 

SDR: An abbreviation for "standard dimensional ratio" that relates to a specific ratio of the average specified 
outside diameter to the minimum wall thickness for outside controlled diameter plastic pipe. 

Seepage Well or Pit: See "Leaching Well" 

Septic Tank: A watertight receptacle that receives the discharge of a building sanitary drainage system or part 
thereof; and that is designed and constructed so as to separate solids from the liquid, digest organic matter through 
a period of detention, and allow the liquids to discharge into the soil outside of the tank through a system of open 
joint or perforated piping, or a seepage pit. See Figure 1.2.52 and Section 16.6 



Comment: Figure 1.2.52 shows baffles at the inlet and outlet connections with two access covers. 
Figure 16.6.6 shows 6" long drop pipes on the inlet and outlet connections with cleanouts and a single 
access cover. Both arrangements perform the same functions and either arrangement is acceptable. 



2006 National Standard Plumbing Code-Illustrated 



47 



-ACCESS COVER 




— — X OUTLET 
TO 
ABSORPTION 
AREA 



Figure 1.2.52 
A TYPICAL SEPTIC TANK 

Service Sink: A sink or receptor intended for custodial use that is capable of being used to fill and empty a 
janitor's bucket. Included are mop basins, laundry sinks, utility sinks, and similar fixtures. (See Table 7.21 . 1) 

Sewage: Liquid containing human waste (including fecal matter) and/or animal, vegetable, or chemical waste 
matter in suspension or solution. 

Sewage Ejector, Pneumatic Type: A unit that uses compressed air to discharge and lift sewage to a gravity 
sewage system. See Sections 11.7 and 12.14.3 

Sewage Pump or Pump-Type Ejector: A non-clog or grinder-type sewage pump or ejector. Sewage pumps 
and pump-type ejectors are either the submersible or vertical type. See Figure 1.2.54 and Section 11.7 



Comment: Figure 1.2.54 shows a pedestal-type sewage pump. Sewage pumps can also be submersible 
pumps or dry pit centrifugal pumps. 



DISCHARGE 
OUTLET - 



LEVEL CONTROL SWITCH 
AND HIGH LEVEL ALARM 



FROM BUILDING 
SUB- DRAIN —\ 



INLET-^ 



FLOAT 




VENT 
SECTION 11.7.4 



AIR TIGHT COVER 



WATER-TIGHT 
DRAINAGE SUMP 



Figure 1.2.54 
A PEDESTAL TYPE SEWAGE PUMP 



48 



2006 National Standard Plumbing Code-Illustrated 



Shall: "Shall" is a mandatory term. 

Shock Arrestor (mechanical device): A device used to absorb the pressure surge (water hammer) that occurs 
when water flow is suddenly stopped. See Figure 10.14.7 and Section 10.14.7 for Water Hammer Arres- 
ters. Also Figure 1.2.3 



Comment: Water hammer arrestors are either the bellows or piston type and are pre-charged with 
compressed air or gas. The Code no longer mentions air chambers, which are subject to losing their 
initial captive air charge through absorption into the system water. 



Short Term: A period of time not more than 30 minutes. 

Side Vent: See "Vent, Side" 

Sink, Commercial: A sink other than for a domestic application. Commercial sinks include, but are not limited to: 

1 . pot sinks 

2. scullery sinks 

3. sinks used in photographic or other processes 

4. laboratory sinks 

Size of Pipe and Tubing: The nominal inside diameter in inches as indicated in the material standards in Table 
3.1.3. If outside diameter is used, the size will be followed by "o.d.". 

Size of Pipe and Tubing, Incremental: Where relative size requirements are mentioned, the following schedule 
ofsizes is recognized, even if all sizes may not be available commercially: 1/4,3/8, 1/2,3/4, 1, 1-1/4, 1-1/2,2,2-1/2, 
3,3-1/2,4,4-1/2,5,6,7,8,10,12,15,18,21,24. 

Slip Joint: A connection in drainage piping consisting of a compression nut and compression washer that permits 
drainage tubing to be inserted into the joint and secured by tightening the compression nut. Slip joints are typically 
used in trap connections for lavatories, sinks, and bathtubs. They permit the trap to be removed for cleaning or 
replacement, and to provide access to the drainage piping. 

Slope: See "Grade" 

Soil Pipe or Soil Stack: Pipes that convey sewage containing fecal matter to the building drain or building sewer. 

Special Wastes: Wastes that require special treatment before entry into the normal plumbing system. See 
Figures 1.2.55 and 9.4.1. Also Section 9.4 



Comment: Figure 1.2.55 shows a neutralizing tank for acid waste using limestone or marble chips. 
Figure 9.4.1 shows an automatic neutralizing tank that could treat either acid or caustic wastes, depend- 
ing on the neutralizing solution used. 



2006 National Standard Plumbing Cade-Illustrated 49 



ACCESS COVER 
FJL 



INLET- 



SIDE OR TOP VENT 




^~^y~\tg* ~7~\yy~\9i ^< 

?//?///////y///////////y////5w7f//J 



OUTLET- 



FILL LEVEL OF 
LIMESTONE OR 
MARBLE CHIPS 
2" x 3" 



Figure 1.2.55 
A NEUTRALIZING OR DILUTION TANK FOR SPECIAL WASTE 

Special Waste Pipe: Pipes which convey special wastes. See Section 3.11 for acceptable piping materials 



Stack: A general term for any vertical line including offsets of soil, waste, vent or inside conductor piping. This 
does not include vertical fixture and vent branches that do not extend through the roof or that pass through not 
more than two stories before being reconnected to the vent stack or stack vent. See Figure 1.2.56, Section 
11.5.2, and Table 11.5.1B 



Comment: Stacks include soil stacks, waste stacks, vent stacks, and stack vents. See separate definitions. 



y 
i 

r+- 



VENT STACK - 



SECOND STORY 



-STACK VENT 



I 

I 

LAV | LAV 



DRINKING 
FOUNTAIN I. 



FIRST STORY - 



\ 



BASEMENT 



W.C. W.C. W.C. 

— o— — o o- 



- SOIL STACK 



f 



W.C. W.C. 

— o— — © 



I I I 
I I I 

LAV I LAV | LAV | 



Figure 1.2.56 
A STACK VENT 



50 



2006 National Standard Plumbing Code-Illustrated 



Stack Group: A group of fixtures located adjacent to the stack so that by means of proper fittings, vents may be 
reduced to a minimum. See Section 12.11 for stack venting groups of fixtures 

Stack Vent: The extension of a soil or waste stack above the highest horizontal drain connected to the stack. 
See Figure 1.2.56 

Stack Venting: A method of venting a fixture or fixtures through the soil or waste stack. See Figure 1.2.57 
and Section 12.11 



VENT 



LAVATORY 




TUB/SHOWER 



WATER 
CLOSET 



Figure 1.2.57 
STACK VENTING 



Standpipe (indirect waste receptor): A vertical drain pipe that has an open top inlet that provides an air break 
or air gap for indirect waste discharge. 



Storm Drain: See "Drain, Storm" 

Storm Sewer: A sewer used for conveying rainwater, surface water, condensate, cooling water, or similar liquid 
wastes. 

Subsoil Drain: A drain that collects subsurface or seepage water and conveys it to a place of disposal. See 
Figure 1.2.59 and Section 13.1.5 for foundation drains 



Comment: Refer to Table 3.8 for acceptable materials for subsoil drains. 



2006 National Standard Plumbing Code-Illustrated 



51 




SUMP WITH 
SUMP PUMP TO 
COLLECT AND 
DISCHARGE CLEAR 
WATER WASTES 
(Section 13.1.5) 



Figure 1.2.59 
SUBSOIL DRAIN PIPING 

Suction Line: The inlet pipe to a pump on which a negative pressure may exist under design conditions. 

Sump: A tank or pit that receives only liquid wastes, located below the elevation of a gravity discharge, that is 
emptied by pumping. 

Sump, Drainage (sewage): A liquid and air-tight tank that receives sewage and/or liquid waste, located below 
the elevation of a gravity drainage system, that is emptied by pumping. See Figure 1.2.54 

Sump Pump: A permanently installed mechanical device for removing clear water or liquid waste from a sump. 
See Figure 1.2.60 



LIFTING HANDLE 



SEALED MOTOR 



SCREEN 




MOTOR- 
PEDESTAL 
DRIVE SHAFT 



-DISCHARGE 



PUMP BODY 




SWITCH 



FLOAT 



INLET SCREEN 
DISCHARGE 



A. SUBMERISBLE TYPE 



B. PEDESTAL TYPE 



Figure 1.2.60 
DIFFERENT TYPES OF SUMP PUMPS 



52 



2006 National Standard Plumbing Code-Illustrated 



Supports: Devices for supporting and securing pipe, fixtures and equipment. See Chapter 8 

Swimming Pool: Any structure, basin, chamber or tank containing a body of water for swimming, diving, or 
recreational bathing. See Section 9.1.11 

Tempered Water: A mixture of hot and cold water to reach a desired temperature for its intended use. 

Thermostatic/Pressure Balancing Valve, Combination: A mixing valve that senses outlet temperature and 
incoming hot and cold water pressure and compenstates for fluctuations in incoming hot and cold water tempera- 
tures and/or pressures to stabilize its outlet temperatures. 



Comment: Combination thermostatic/pressure balancing control valves are used for individual bathing 
facilities and must comply with ASSE 1016, Type PT. 



Thermostatic (Temperature Control) Valve: A mixing valve that senses outlet temperature and compensates 
for fluctuations in incoming hot or cold water temperatures. 



Comment: Thermostatic control valves used for individual bathing facilities must comply with ASSE 
1016, Type T. Thermostatic control valves for other point-of-use applications should comply with the 
appropriate standard. 



Toilet Facility: A room or combination of interconnected spaces in other than a dwelling that contains one or 
more water closets and associated lavatories, with signage to identify its intended use. 

Trap: A fitting or device that provides a liquid seal to prevent the emission of sewer gasses without materially 
affecting the flow of sewage or waste water through it. See Figure 1.2.62 and Sections 5.1, 5.2, and 5.3 



-INLET 




CROWN WEIR OF TRAP 



OUTLET 

TRAP 
-SEAL 



TRAP DIP 



Figure 1.2.62 
ELEMENTS OF A FIXTURE TRAP 



j Trap Arm: That portion of a fixture drain between a trap and its vent. See Figure 1.2.63 and Section 12.8.1 



Comment: Refer to Table 12.8.1 for the maximum allowable length of trap arms to avoid trap siphonage. 



2006 National Standard Plumbing Code-Illustrated 



53 




DISTANCE FROM 
TRAP TO VENT 



./ 



% 



TRAP WEIR 



INSIDE WALL 
OF PIPE 

— VENT 

— TOP OF VENT OPENING 

— WASTE 



NOTES: 

1 . The top of the opening to the vent at the end of the trap arm must not be below the weir of the trap. 

Figure 1.2.63 
THE LENGTH OF A TRAP ARM 
Trap Primer: A device or system of piping to maintain a water seal in a trap. See Figures 1.2.64 and 1.2.65. 
Also Section 7.16.2 



SUPPLY — 




TO FIXTURE 



INTEGRAL AIR GAP 



TO TRAP 



Figure 1.2.64 
A FLOW-ACTIVATED TRAP PRIMER 



POTABLE WATER LINE 



TRAP PRIMER 




TRAP SEAL —j=? TRAP ARM 
TRAP- 



Figure 1.2.65 
CONNECTION OF A TRAP PRIMER TO A TRAP 



54 



2006 National Standard Plumbing Code-Illustrated 



Trap Seal: The maximum vertical depth of liquid that a trap will retain, measured between the crown weir and 
the top of the dip of the trap. See Figure 1.2.62 and Section 5.3.2 

Vacuum: Any pressure less than that exerted by the atmosphere. 

Vacuum Assisted Water Closet: See "Water Closet, Vacuum Assisted" 

Vacuum Breaker: See "Backflow Preventer" 



Vacuum Breaker, Atmospheric Type: A vacuum breaker that is not designed to be subject to static line 
pressure. See Figure 1.2.66 




A. THREADED TYPE ATMOSPHERIC 



B. HOSE TYPE ATMOSPHERIC 



Figure 1.2.66 
TYPES OF ATMOSPHERIC VACUUM BREAKERS 



Vacuum Breaker, Pressure Type: A vacuum breaker designed to operate under conditions of static line 
pressure. See Figure 1.2.67 







Figure 1.2.67 
A PRESSURE TYPE VACUUM BREAKER 

Vacuum Breaker, Spill-resistant (SVB): A pressure-type vacuum breaker specifically designed to avoid 
spillage during operation, consisting of one check valve force-loaded closed and an air inlet vent valve force-loaded 
open to atmosphere, positioned downstream of the check valve, and located between and including two tightly 
closing shut-off valves and a means for testing. 



2006 National Standard Plumbing Code-Illustrated 



55 



Comment. SVB vacuum breakers are spill-resistant, not spill-proof. 



Vacuum Relief Valve: A device to prevent vacuum in a pressure vessel. See Figure 1.2.69 and Section 
10.16.7 



Comment: Vacuum relief valves are required on storage-type hot water heaters that are located above 
the fixtures that they serve to prevent the tank from being siphoned dry and damaged by dry-firing. 



Figure 1.2.69 

A VACUUM RELIEF VALVE 

Vent, Branch: A vent connecting one or more individual vents with a vent stack or stack vent. See Figure 
1.2.70 



h- 



w.c. 



• BRANCH VENT - 

URINAL 



I I IIPIKIAI 



/ 



) 



W.C. 



^ 



I LAV 



) 



VH ^ 



LAV 



=r 



Figure 1.2.70 
A BRANCH VENT 

Vent, Circuit: A vent that connects to a horizontal drainage branch and vents from two to eight traps or trapped 
fixtures connected in a battery. See Figure 1.2.71 



Comment: Circuit vents connect to vent stacks. Loop vents connect to stack vents. 



56 



2006 National Standard Plumbing Code-Illustrated 



RELIEF 
VENT - 



- SOIL STACK 



VENT STACK 



r" 



r 



I 



t 



J 



i 

CIRCUIT VENT 



W.C. 



W.C. 



W.C. 



g g g 



I 



W.C. 



~0 



Figure 1.2.71 
A CIRCUIT VENT 
Vent, Common: A vent connected at the common connection of two fixture drains and serving as a vent for 
both fixtures. See Figure 1.2.72 



LAV 



Y- 



- COMMON VENT 
LAV 



^ 



Figure 1.2.72 
A COMMON VENT 
Vent, Continuous: A vertical vent that is a continuation of the drain to which it connects. See Figure 1.2.73 



LAV 



^ 



CONTINOUS VENT 



FIXTURE DRAIN 
i 



Figure 1.2.73 
A CONTINUOUS VENT 

Vent, Dry: A vent that does not receive the discharge of any sewage or waste. 

Vent, Individual: A pipe installed to vent a single fixture drain. See Figure 1.2.74 



2006 National Standard Plumbing Code-Illustrated 



57 



r 



LAV 

c=3 






•INDIVIDUAL VENT 



TRAP ARM - 



-FIXTURE DRAIN 

— i 



Figure 1.2.74 
AN INDIVIDUAL VENT 

Vent, Loop: A circuit vent that loops back to connect with a stack vent instead of a vent stack. See Figure 
1.2.75 



Comment: Loop vents connect to stack vents. Circuit vents connect to vent stacks. 



LOOP VENT- 






-1~ 
I 
I 
'1 



w.c. 


w.c. 


1 
1 

W.C. | 


Vf 


ft 


Yi 


G ' 


— 4 — 


1 

1 
— e 1 



-STACK VENT 



1 



Figure 1.2.75 
A LOOP VENT 



Vent, Relief: An auxiliary vent that permits additional circulation of air in or between a drainage and vent 
system. See Figures 12.3.1, 12.3.2, 12.3.3-A, 12.3.3-B, 12.13.1, 12.15.1, and 12.16.2 



Comment: Relief vents are required at points in some vertical drainage stacks, at horizontal offsets in 
some drainage stacks, at the base of some stacks, and at some batter}' vented branch connections to 
stacks. Refer to Chapter 12. 



Vent, Side: A vent connecting to a drain pipe through a fitting at an angle not greater than 45° to the vertical. 
See Figure 1.2.76 



58 



2006 National Standard Plumbing Code-Illustrated 



*>* 



"V 



VERTICAL DRAIN - 



■ SIDE VENT 



NOT LESS THAN 45° _ 
ABOVE HORIZONTAL 



> 



Q 




HORIZONTAL DRAIN 



Figure 1.2.76 

SIDE VENTS 

Vent, Sterilizer: A separate pipe or stack, indirectly connected to the building drainage system at the lower 
terminal, that receives the vapors from non-pressure sterilizers, or the exhaust vapors from pressure sterilizers and 
conducts the vapors directly to the outer air. Sometimes called vapor, steam, atmosphere or exhaust vent See 
Section 14.11 



Vent, Wet: A vent that receives the discharge of wastes from fixtures other than water closets or kitchen sinks 
See Figure 1.2.77. Refer to Section 12.10 for other arrangements of wet venting. 



T 

I 

i 



| LAVATORY 



WATER 
CLOSET 



-WET VENT 



Figure 1.2.77 
A WET VENT 

Vent, Yoke: A pipe connecting upward from a soil or waste stack to a vent stack for the purpose of equalizing 
the pressures in the stacks. See Figure 1.2.78 " 



Comment: A yoke vent is vertical No portion of a yoke vent can be horizontal. 



2006 National Standard Plumbing Code-Illustrated 



59 



r 



VENT STACK *\ 

i 12.3.1) -^ I 



(Section ' 



\ 



X. 



-YOKE VENT 

^-SOIL OR WASTE STACK 



Figure 1.2.78 
A YOKE VENT 



Vent Pipe: Part of the vent system. 



Vent Stack: A vertical vent pipe that extends through one or more stories and that is intended to provide circula- 
tion of air to and from the drainage system. See Figures 1.2.71 and 12.3.1 

Vent System: A pipe, or pipes, installed to provide a flow of air to or from a drainage system or to provide a 
circulation of air within such system to protect trap seals from siphonage and back pressure. See Figure 1.2.79 

VERTICAL 



VERTICAL PIPE (45° OR MORE) 




HORIZONTAL PLANE 



VERTICAL 



Figure 1.2.79 
THE DEFINITION OF "VERTICAL PIPE" 



60 



2006 National Standard Plumbing Code-Illustrated 



Vertical Pipe: Any pipe or fitting that makes an angle of 45° or more with the horizontal. See Figure 1.2.79 



Wall Hung Water Closet: A water closet installed in such a way that no part of it touches the floor. See 
Figure 1.2.80 



WALL ' 




/////;////// 



~7~7' /////////// 



Figure 1.2.80 
A WALL HUNG WATER CLOSET 

Waste: Any remaining liquid, or liquid-borne material or residue intended to be discharged to the drainage system 
after any activity or process, but not including any such materials that contain animal or human fecal matter. 

Waste Pipe: A pipe that conveys only waste. 

Waste Stack, Pipe or Piping: Pipes that convey the discharge from fixtures (other than water closets), appli- 
ances, areas, or appurtenances, that do not contain fecal matter. 

Water Closet, Pressure Assisted: A low consumption water closet with an air accumulator vessel in the tank 
that stores water and air under pressure, using the water supply pressure. When flushed, the air produces a high 
velocity jet of water and air that forces the contents out of the bowl. 

Water Closet, Pump Assisted: A low consumption water closet with a fractional horsepower pump in the tank 
that produces a high velocity jet in the trap way that assists the flushing action. 

Water Closet, Vacuum Assisted: A low consumption water closet that uses the falling water level in the tank 
to induce a vacuum near the outlet of the trap way that assists the flushing action. 

Water Distribution Piping: Piping within the building or on the premises that conveys water from the water- 
service pipe to the point of use. See Figure 1.2.81 



2006 National Standard Plumbing Code-Illustrated 



61 



n> 



BATHTUB 



LAVATORY 



TO UPPER FLOORS 

T 



w.c. 



u 




TO FIXTURES 




L^£ 



rr 



WATER DISTRIBUTION 
RISERS 



rvj 



WATER DISTRIBUTION 
BRANCHES 



'^. 



J> 




FROM SOURCE 



COLD 

HOT 

Figure 1.2.81 
WATER DISTRIBUTION PIPING 

Water Lifts: See "Sewage Ejector" 

Water Main: A water supply pipe for public use. See "Public Water Main" 

Water Outlet: A discharge opening through which water is supplied to a fixture, into the atmosphere (except 
into an open tank that is part of the water supply system), to a boiler or heating system, to any devices or equip- 
ment requiring water to operate but that are not part of the plumbing system. 



62 



2006 National Standard Plumbing Code-Illustrated 



Water Riser Pipe: See "Riser" 



Water Service Pipe: The pipe from the water main, or other source of potable water supply, to the water 
distribution system of the building served. See Figure 1.2.82 and Section 10.6 



STREET 



CURB BOX OR 
WATER METER 
AT PROPERTY LINE 



CORPORATION 
COCK- 



z 



^ 




f 



APPROVED 

SHUT-OFF 

VALVE (Section 10.12.1) 



-WATER DISTRIBUTION PIPING 



-BUILDING 
VALVE AND DRAIN 
(Section 10.12.2) 



r.'v- : w-U 



*±^t 



• SLEEVE AND SEALANT 
(Section 10.6.4) 



-WATER SERVICE PIPE TO BUILDING 



Figure 1.2.82 
THE WATER SERVICE PIPE IN A PUBLIC WATER SUPPLY 



Water Supply System: The water service pipe, the water distribution pipes, and the necessary connecting pipes, 
fittings, control valves, and appurtenances in or adjacent to the building or premises. 

Water Temperature Control Valve: A valve of the pressure balance, thermostatic mixing, or combination 
pressure balance/thermostatic mixing type that is designed to control water temperature to reduce the risk of 
scalding. 



Wet Vent: See "Vent, Wet" 

Whirlpool Bathtub: A plumbing appliance consisting of a bathtub fixture that is equipped and fitted with a 
circulation piping system, pump, and other appurtenances and is so designed to accept, circulate, and discharge 
bathtub water upon each use. See Figure 1.2.83 




-/-'/—/—/-/--/ 7-7~7--pr-7- 7 -y^-y— r - 7 -- 7 — / 



Figure 1.2.83 
A WHIRLPOOL BATH 



2006 National Standard Plumbing Code-Illustrated 



63 



Weir (trap or crown) Discharge overflow of the trap outlet. 
Yoke Vent See "Vent, Yoke: 



64 2006 National Standard Plumbing Code-Illustrated 



General Regulations 



2.1 RESERVED 

2.2 RESERVED 

2.3 CHANGES IN DIRECTION OF DRAINAGE PIPING 
2.3.1 Uses for Drainage Fittings 

a. Changes in direction of drainage piping shall be made with long radius drainage fittings. See Table 

EXCEPTION: Short radius drainage fittings shall be permitted in the drain piping for individual fixtures See 
Table 2.3.1. 

b. Short radius drainage fittings are those having radius or centerline dimensions that are approximately 
equal to or less than their nominal pipe size. The radius or centerline dimensions of long radius drainage 
fittings are greater than their nominal pipe size. 

c. Long radius drainage fittings shall not be used to connect fixture trap amis to vertical drain and vent 
piping. Connections to fixture vents shall be above the top weir of the fixture trap 

See Figures 2.3.1-A, 2.3.1-B, 2.3.1-C, and 2.3.1-D 



VERTICAL 




VERTICAL 




£ 



VERTICAL 



VERTICAL 




SANITARY TEE 



NOTES: 



WYE AND 1/8 BEND 



SWEEP OR 
QUARTER BEND 







DOUBLE COMBINATION 



HORIZONTAL 



1 . Horizontal-to-vertica! changes in direction are not as critical as other changes because gravity 
controls the velocity in vertical drops. 

2. No-hub cast iron fittings are shown. SeeTable2.3.1 for fitting patterns for other drainaqe pipe 
materials. 

3. Short pattern fittings are permitted in piping for individual fixtures. 

4. Long pattern fittings are not permitted to connect fixture trap arms to vertical and vent piping 
because the vent opening at the end of the trap arm will be below the weir of the trap causinq the 
trap to self-siphon. 

Figure 2.3.1 - A 

DRAINAGE FITTINGS FOR HORIZONTAL-TO-VERTICAL 

CHANGES IN DIRECTION 



2006 National Standard Plumbing Code-Illustrated 



65 



90° LONG SWEEP 
OR LONG 1/4 BEND 




COMBINATION WYE 
& 1/8 BEND 



PLAN VIEW 



NOTES: 

1 Long pattern fittings are required except short pattern fittings are permitted for individual fixtures. 
2. No-hub cast iron fittings are shown. See Table 2.3.1 for fitting patterns for other drainage pipe 
materials. 



Figure 2.3.1 - B 

DRAINAGE FITTINGS FOR HORIZONTAL-TO-HORIZONTAL 

CHANGES IN DIRECTION 



VERTICAL 



VERTICAL 



VERTICAL 




L LONG SWEEP 
QUARTER BEND 
TO BE EQUIVALENT 
TO WYE AND 
1/8 BEND 



WYE AND 1/8 BEND 



COMBINATION WYE 
AND 1/8 BEND 



HORIZONTAL 



ELEVATION VIEW 



NOTES: 

1 . Long pattern fittings are required except short pattern fittings are permitted for individual fixtures. 

2. No-hub cast iron fittings are shown. SeeTable2.3.1 for fitting patterns for other drainage pipe 

materials. 

3. See Sections 11.11 and 12. 15 for restrictions on branch drain connections near the base of stacks 

that are subject to suds pressure. 

Figure 2.3.1 - C 

DRAINAGE FITTINGS FOR VERTICAL-TO-HORIZONTAL 

CHANGES IN DIRECTION 



66 



2006 National Standard Plumbing Code-Illustrated 





Table 2.3.1 PERMISSIBLE D 


RAINAGE FITTINGS FOR CHANGE 


S IN DIRECTION 


PIPE 
MATERIAL 


CHANGE IN DIRECTION 


HORIZONTAL 

TO 
HORIZONTAL 


HORIZONTAL 

TO 

VERTICAL 


VERTICAL 

TO 

HORIZONTAL 


CAST IRON 

HUB 

& 

SPIGOT 

CAST IRON 
NO-HUB 


long sweep 


sanitary tee (1) 


eighth bend and wye 


short sweep 


eighth bend and wye (2) 


combination wye & eighth bend 


wye 


combination wye & eighth bend (2) 


long sweep 


combination wye & eighth bend 


long sweep 


short sweep 3" or larger 


fifth bend (72-deg) 


short sweep 


quarter bend (1) 


sixth bend (60-deg) 


quarter bend (1) 


short sweep ( 1 ) 


eighth bend (45-deg) 






sixteenth bend (22 '/•> deg) 


quarter bend (1) 


CAST IRON 
DRAINAGE 

(threaded) 


extra long turn 90-deg elbow 


drainage tee (1) 


long turn 90-deg TY 


long turn 90-deg elbow 


short turn 90-deg TY(1) 


extra long turn 90-deg elbow 


long turn 45-deg elbow 


long turn 90-deg TY (2) 


long turn 90-deg elbow 


short turn 22 Vi deg elbow 


45-deg elbow and 45-deg Y branch (2) 


short turn 90-deg elbow (1) 


short turn 1 1 'A deg elbow 


extra long turn 90-deg elbow 


45-deg elbow & 45-deg Y branch (1) 


long turn 90-deg TY 


long turn 90-deg elbow 




short turn 45-deg Y branch 


short rum 90-deg elbow (1) 


short turn 90-deg elbow (1) 




short turn 60-deg elbow (1) 


short turn 45-deg elbow (1) 


COPPER 
DWV 


DWV 90-deg long radius elbow 


DWV tee (1) 


DWV long turn T-Y 


90-deg elbow - long radius 


DWV 90-deg sanitary tee (1) 


45-deg elbow and DWV 45-deg Y 


DWV long turn T-Y 


DWV long turn T-Y (2) 


DWV 90-deg long radius elbow 


DWV 45-deg Y 


45-deg elbow & DWV 45-deg Y (2) 


90-deg elbow - long radius 


DWV 90-deg elbow (1) 


DWV 90-deg long radius elbow 


DWV 90-deg elbow (1) 


DWV 45-deg elbow (1) 


90-deg elbow - long radius 






DWV 90-deg elbow (1) 


PLASTIC 
DWV 


90-deg long turn elbow 


sanitary tee (1) 


long radius TY 


long sweep 1 /4 bend 


fixture tee (1) 


45-deg elbow and 45-deg wye 


60-deg elbow or 1/6 bend 


long radius TY (2) 


90-deg long turn elbow 


45-deg elbow or 1/8 bend 


45-deg elbow and 45-deg wye (2) 


90-deg elbow or 1/4 bend (1) 


22 '/2 deg elbow or 1/16 bend 


90-deg long turn elbow 




long radius TY 


90-deg elbow or 1/4 bend (1) 


45-deg wye 




90-deg elbow or 1/4 bend (1) 


STAINLESS 
STEEL 

push-fit 
DWV 


long sweep 


tee(l) 


eighth bend & wye (2) 


wye 


sanitary tee (1) 


combination wye & eighth bend 


combination wye & eighth bend 


eighth bend & wye (2) 


long sweep 


15-degree 1/24 bend 


combination wye & eighth bend 


90-degree 1/4 bend (1) 


22 Vi degree 1/16 bend 


long sweep 




30-degree 1/12 bend 


90-degree 1/4 bend (1) 


45-degree 1/8 bend 




90-degree 1/4 bend (1) 



Footnotes for Table 2.3. 1 

(1) Short radius fittings shall be permitted only in drain piping for individual fixtures. 

(2) Long radius fittings shall not be used to connect fixture trap arms to vertical drain and vent piping. 



2006 National Standard Plumbing Code-Illustrated 



67 



FROM FIXTURES 
UPSTREAM 



SHORT PATTERN 
(Section 2.3.1) 




LONG PATTERN 
(Section 2.3.1) 



SHORT PATTERN 



SHORT PATTERN 

FROM FIXTURES UPSTREAM 



NOTES: 

1 . Short pattern fittings are permitted in drain piping for individual fixtures. 

2. Long pattern fittings are not permitted to connect fixture trap arms to vertical drain and vent piping 
because the vent opening at the end of the trap arm will be below the weir of the trap, causing the 
trap to self-siphon. 

Figure 2.3.1 - D 
USE OF SHORT AND LONG PATTERN DRAINAGE FITTINGS 



2.3.2 Double Pattern Fittings 

The uses for double pattern drainage fittings shall be the same as for single pattern fittings in Table 2.3.1 . 
EXCEPTION: Double sanitary tees and crosses shall not be used to connect blowout fixtures, back-outlet 
water closets, and fixtures or appliances having pumped discharge. See Figure 2.3.2 




Y. 



DOUBLE FIXTURE FITTING - ENLARGED 

CHAMBER TO PREVENT CROSS-FLOW FROM 

ONE FIXTURE TO ANOTHER 



DOUBLE COMBINATION WYE & 1/8 BEND 

HORIZONTAL DRAINAGE TO 

VERTICAL DRAINAGE 



NOTES: 

1. 

2. 



Double pattern fittings can be used in horizontal and vertical piping. 

Long pattern fittings are not permitted to connect fixture trap arms to vertical drain and vent piping 
because the vent opening at the end of the trap arm will be below the weir of the trap, causing the 
trap to self-siphon. 

Figure 2.3.2 
DOUBLE PATTERN DRAINAGE FITTINGS 



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2006 National Standard Plumbing Code-Illustrated 



2.3.3 Back-to-Back Fixtures 

Stack fittings, including carriers, for back-outlet fixtures installed back-to-back shall be either the wye pattern, 
incorporate baffles within the drainage fitting, or otherwise be designed to prevent crossflow or mixing of the ' 
discharges from the two fixtures prior to the change in direction. See Figure 2.3.3 



VERTICAL 



2" 

TOP VENT 




FIXTURE 
INLET 



BAFFLE BETWEEN 
FIXTURE INLETS 



STACK 
INLET 




STACK 
OUTLET 



BAFFLE BETWEEN INLETS 



FIXTURE 
INLET 



PART A 



VENTED CLOSET CROSS WITH 
2 " TOP VENT 



VERTICAL 
STACK 



FIXTURE 
INLET 




VERTICAL 
STACK 



FIXTURE 
INLET 



FIXTURE 
INLET 



HORIZONTAL 
BRANCH 




HORIZONTAL 
BRANCH 



FIXTURE 
INLET 



PARTB 



DOUBLE COMBINATION WYE & 1/8 BEND 
HORIZONTAL - TO - VERTICAL 



PARTC 



DOUBLE COMBINATION WYE & 1/8 BEND 
HORIZONTAL - TO - HORIZONTAL 



NOTES: 



1. No-hub cast iron fittings are shown. SeeTable2.3.1 for fitting patterns for other drainage pipe 
materials. 

2. In Part B, the fixtures must be vented prior to connection to the stack. 

3. In Part C, if not battery vented, the fixtures must be individually vented prior to connection to the 
branch drain. 

Figure 2.3.3 
PREVENTING CROSSFLOW BETWEEN BACK-TO-BACK BACK-OUTLET FIXTURES 



2006 National Standard Plumbing Code-Illustrated 



69 



2.4 FITTINGS AND CONNECTIONS IN DRAINAGE SYSTEMS 

2.4.1 Prohibited Fittings 

No running threads or saddles shall be used in the drainage or vent system. No drainage or vent piping shall 
be drilled, tapped, burned or welded. 



2.4.2 Heel or Side-Inlet Bends 

A heel or side-inlet quarter bend shall not be used as a dry vent when the inlet is placed in a horizontal 
position or any similar arrangement of pipe or fittings producing a similar effect. 

EXCEPTION: When the entire fitting is part of a dry vent arrangement system the heel or side-inlet bend 
shall be acceptable. See Figures 2.4.2-A and 2.4.2-B 

VENT 




PROHIBITED IF NOT 
A WET VENT 




PROHIBITED IF NOT 
A WET VENT 



SIDE INLET 
HEEL INLET 

Figure 2.4.2 - A 
HORIZONTAL HEEL OR SIDE INLET VENT CONNECTION 










feSSSSSSSLES^^ 




DRY VENT IS ACCEPTABLE 
IF HEEL INLET IS VERTICAL 



HEEL INLET 



Figure 2.4.2 - B 
VERTICAL HEEL INLET VENT CONNECTION 
2.4.3 Obstruction to Flow 

a. No fitting, connection, device, or method of installation that obstructs or retards the flow of water, 
wastes, sewage, or air in the drainage or venting systems in an amount greater than the normal frictional 
resistance to flow, shall be used unless it is indicated as acceptable in this Code. 



70 



2006 National Standard Plumbing Code-Illustrated 



b. 4x3 closet bends and 4x3 closet flanges shall not be considered as obstructions to flow. 



Comment #1: This Section does not prohibit double hub fittings for soil pipe installations since they 
create no more restriction to flow that would be encountered with a hitbless coupling or similar fitting. 

Comment #2: Failure to ream or deburr drainage piping constitutes an obstruction to flow. 



2.4.4 ProhibitedJoints 

Cement mortar joints are prohibited. 

EXCEPTION: When used for repairs and/or when used for connections to existing lines constructed with 
suchjoints. 

2.5 HEALTH AND SAFETY 

Where a health or safety hazard is found to exist on a premise, the owner or his agent shall be required to make 
such corrections as may be necessary to abate such nuisance, and bring the plumbing installation within the 
provisions of this Code. 

2.6 TRENCHING, BEDDING, TUNNELING AND BACKFILLING 

2.6.1 Trenching and Bedding 

a. Trenching and excavation for the installation of underground piping shall be performed in compliance 
with occupational safety and health requirements. Trenches shall be of sufficient width to permit proper 
installation of the pipe. Where shoring is required, additional allowance shall be made in the width of the 
trench to provide adequate clearance. 

b. A firm, stable, uniform bedding shall be provided under the pipe for continuous support. Bell holes shall 
be provided for joints in bell and spigot pipe and for other joints requiring such clearance. Blocking shall not be 
used to support the pipe. 

c. The trench bottom may provide the required bedding when adequate soil conditions exist and when 
excavated to the proper depth and grade. Where trenches are excavated to depths below the bottom of the 
pipe, bedding shall be added beneath the pipe as required. Such bedding shall be of clean sand, gravel, or 
similar select material that is compacted sufficiently to provide the support required under 2.6. 1 .b. 

d. Where rock is encountered in trenching, it shall be removed to a depth of not less than 6 inches below 
the bottom of the pipe and bedding shall be added as required under 2.6. I.e. The pipe shall not rest on rock at 
anypoint, includingjoints. 

See Figures 2.6.1-A and 2.6.1-B. Also Sections 2.6.2, 2.6.3, and 2.6.4 



2006 National Standard Plumbing Code-Illustrated 



71 



GRADE 



f 



m 



[ 



SIDE-FILL 



^ SOIL BEDDING 



GRADE 

1 . mmiMmmmmmmmmmmmmm 



tz 



i 



BACKFILL 



SOIL BEDDING 



PIPE BELLS OR COUPLINGS 



NOTES: 

1. The soil under the pipe must be stable. Unstable bedding may damage the pipe, fittings, or joints 
when settlement occurs. 

2. The side-fill should be shoveled under the pipe to make sure that there are no voids in the side-fill. 

Figure 2.6.1 - A 
UNDERGROUND PIPING BEDDED ON SOIL 



GRADE 

~ P« 




GRADE 

__ ™ 



SIDE-FILL 



BACKFILL 




^^Miiiiifetesi 1 



- — SAND OR GRAVEL 
|- BEDDING 



SAND OR GRAVEL BEDDING 



NOTES: 

1 . Unstable bedding may damage the pipe, fittings, or joints when settlement occurs. 

2. The side-fill should be shoveled under the pipe to make sure that there are no voids in the side-fill. 

Figure 2.6.1 - B 
UNDERGROUND PIPING BEDDED ON SAND OR GRAVEL 



2.6.2 Side-fill 

The haunch areas adjacent to the pipe between the bottom of the pipe and its horizontal centerline shall be 
filled with a clean coarse-grain material such as sand, gravel, or soil. Such side-fill shall be placed by hand, 
extending to the sides of the trench, and be compacted to provide lateral support for the pipe. See Figure 
2.6.1-A and 2.6.1-B 



72 



2006 National Standard Plumbing Code-Illustrated 



2.6.3 Initial Backfill 

After installation of the side-fill, the trench shall be backfilled to a level not less than 2 feet above the top of 
the pipe. Backfill material shall be sand, gravel, or loose soil that is free of rocks and debris. Maximum 
particle size shall be 1-1/2 inches. Backfill shall be placed in not more than 6-inch layers, each tamped and 
compacted. Heavy compacting equipment shall not be used for the initial backfill. See Figure 2.6.3 



FINAL BACKFILL (Section 2.6.4) 



::::::::_::::::::::::::::: FILL TAMPED IN 6" 

_ : _ : _,.. : _^ LAYERS UNTIL TWO 

24« I -'-■.-~-~-~-~-~-~-~-~-~ ■--.-.: FEET OF EARTH 
I :::::::::::::::::!::::::::: COVERS THE PIPE 

NOTES! | W*Wi^^^^^^^i^W¥WP«*WWWWVWWWW* 

1 . The side-fill adjacent to the pipe must be backfilled and tamped to the top of the pipe. 

2. The initial backfill must be placed in 6" tamped layers. The use of heavy compacting equipment is 
prohibited. 

3. The initial backfill material must be sand, gravel, or loose soil from the excavation that is free from 
rocks and debris. Broken concrete, frozen earth, and other solid materials may damage the pipe 
from point loads. 

4. After the pipe is covered with 2 feet of tamped initial backfill, the final backfill to grade can be 
compacted with heavy equipment. 

Figure 2.6.3 
TYPICAL BACKFILLING PROCEDURE 

2.6.4 Final Backfill 

The trench shall be backfilled from the top of the compacted initial backfill to finish grade using suitable 
material. Heavy compacting equipment may be used for the final backfill. See Figure 2.6.3 

2.6.5 Tunneling 

When pipe is installed in a dug or bored earth tunnel, the space around the pipe between the pipe and the wall 
of the tunnel shall be completely filled with packed concrete or grout. When pipe is installed in a jacked-in- 
place conduit or sleeve, the space around the pipe between the pipe and the inside of the conduit or sleeve 
shall be sealed in an approved manner in accordance with Section 2.12.d. 

2.6.6 Underground Plastic Pipe 

a. Underground plastic pipe shall be installed in accordance with the requirements of Section 2.6. 
EXCEPTIONS: 

(1) The maximum particle size in the side-fill and initial backfill shall be not more than 1/2-inch for pipe 6" 
size and smaller, and 3/4-inch for pipe 8" and larger. 

(2) For water service piping, refer to ASTM D2774, Standard Practice for Underground Installation 
of Thermoplastic Pressure Piping. 

(3) For gravity-flow drainage pipe, refer to ASTM D2321, Underground Installation of Thermoplastic 
Pipe for Sewers and Other Gravity-flow Applications. 

b. An insulated copper tracer wire or other approved conductor shall be installed adjacent to underground 



2006 National Standard Plumbing Code-Illustrated 73 



non-metallic water service piping and non-metallic force mains, to facilitate finding. One end shall be brought 
above ground inside or outside the building wall. The tracer wire for the water service shall originate at the 
curb valve required in Section 1 0. 12. 1 . The tracer wire for the force main shall originate at the final point of 
disposal. The tracer wire shall not be less than 1 8 AWG insulated. The insulation shall not be yellow in color. 

2.6.7 Underground Copper Piping 

Underground copper piping shall be installed in accordance with the requirements of Section 2.6. 
EXCEPTION: The maximum particle size in the side-fill and initial backfill shall be not more than 1/2-inch for 
pipe 6" size and smaller, and 3/4-inch for pipe 8" and larger. 

2.6.8 Safety Precautions 

Rules and regulations pertaining to safety and protection of workers, other persons in the vicinity, and neigh- 
boring property shall be adhered to where trenching or similar operations are being conducted. 

2.6.9 Supervision 

Where excavation, bedding or backfilling are performed by persons other than the installer of the underground 
piping, the pipe installer shall supervise the bedding, side-fill, and initial backfill, and shall be responsible for its 
conformance to this Code. 

2.6.10 Trenchless Pipe Replacement Systems 

Trenchless replacement of water and sewer piping shall be performed using equipment and procedures 
recommended by the equipment manufacturer. Where underground piping beneath paved surfaces or 
concrete floor slabs is replaced by this method, the manufacturer's recommendations for the specific condi- 
tions shall be used. Approved mechanical couplings shall be used to make the connections between new and 
existing piping. 



Comment: When piping beneath paving or concrete floors is replaced by the trenchless method, there 
must be sufficient distance above the pipe to prevent cracking the paving or floor slab when the pipe 
being replaced bursts. 



2.7 SAFETY 

Any part of a building or premise that is changed, altered, or required to be replaced as a result of the installation, 
alteration, renovation, or replacement of a plumbing system, or any part thereof, shall be left in a safe, non-hazard- 
ous condition. 

2.8 INSTALLATION PRACTICES 

Plumbing systems shall be installed in a manner conforming to this Code and industry installation standards. 

2.9 PROTECTION OF PIPES 

2.9.1 Breakage 

Pipes passing under or through foundation walls shall be protected from breakage. 



2006 National Standard Plumbing Code-Illustrated 



2.9.2 Corrosion 

Pipe subject to corrosion by passing through or under corrosive fill, such as, but not limited to, cinders, con- 
crete, or other corrosive material, shall be protected against external corrosion by protective coating, wrap- 
ping, or other means that will resist such corrosion. 



Comment #1: Soil samples should be taken to assure that the soil will not corrode the pipe. Wrappings 
and coatings reduce contact corrosion, but cathodic protection may be required where stray electric 
currents exist. 

Comment #2: Job site debris should not be allowed in the backfill for piping trenches. Material such as 
metal cans, metal studs, and gypsum board may chemically react with some types of pipe. 



2.9.3 Cutting or Notching 

Any structural member weakened or impaired by cutting, notching, or otherwise, shall be reinforced, repaired 
or replaced, so as to be left in a safe structural condition in accordance with the requirements of the Building 
Code or as required by the proper Authority Having Jurisdiction. 

2.9.4 Penetration 

a. Plastic and copper piping run through framing members to within one inch of the edge of the framing 
shall be protected by steel nail plates not less than 18 gauge. Where such piping penetrates top plates or sole 
plates of the framing, the nail plate shall extend at least two inches below top plates and two inches above 
sole plates. 

b. Where plastic and copper piping runs through metal framing members, it shall be protected from 
abrasion caused by expansion and contraction of the piping or movement of the framing. 

2.10 EXCLUSION OF MATERIALS DETRIMENTAL TO THE 

SEWAGE SYSTEM 

2.10.1 General 

No material shall be deposited into a building drainage system or sewer that would or could either obstruct, 
damage, or overload such system; that could interfere with the normal operation of sewage treatment pro- 
cesses; or that could be hazardous to people or property. This provision shall not prohibit the installation of 
special waste systems when approved by the Authority Having Jurisdiction. 

2.10.2 Industrial Wastes 

Waste products from manufacturing or industrial operations shall not be introduced into the public sewer 
system until it has been determined by the Authority Having Jurisdiction that the introduction thereof will not 
cause damage to the public sewer system or interfere with the functioning of the sewage treatment plant. 



Comment; Where industrial wastes will be created, the facility should provide the following information 
to the Authority Having Jurisdiction for the sewerage system: (1) the quantity of water and waste 
material that will be discharged into the sewer system, (2) the industrial processes that create the waste, 
(3) the composition and concentration of the chemicals in the waste, (4) the water supply demand for the 
facility, and (5) the intended design of the pre-treatment or neutralizing system for the wastes prior to its 
discharge into the sewer system. 



2006 National Standard Plumbing Code-Illustrated 75 



2.11 PIPING MATERIALS EXPOSED WITHIN PLENUMS: 

All piping materials exposed within plenums shall comply with the provisions of other applicable Codes. 



2.12 SLEEVES 

a. All piping passing through concrete walls, floors, slabs, and masonry walls shall be provided with sleeves 
for protection. 

EXCEPTION: Sleeves shall not be required for pipes passing through drilled or bored holes. Such holes shall 
provide 1/2 inch minimum clearance around the pipe and any thermal insulation. 

b. Sleeves shall be sized so there is a minimum of 1/2-inch clearance around the pipe and/or insulation. 

c. Piping through concrete or masonry walls shall not be subject to any load from building construction. 

d. The annular space between sleeves and pipes shall be filled or tightly caulked with coal tar, asphaltum 
compound, lead, or other material found equally effective and approved as such by the Authority Having 
Jurisdiction. 

e. All penetrations of construction required to have a fire resistance rating shall be protected in accordance 
with the applicable building regulations. 

See Figure 2.12 



C 




SLEEVE 
PACKING MATERIAL 



3 



PIPE 




SLEEVES MUST BE SIZED 

SO THERE IS A MINIMUM OF 1/2 INCH 

CLEARANCE AROUND PIPE 



NOTES: 

1 . The sleeve must be sealed where necessary to prevent the entrance of ground water into the 
building. 

Figure 2.12 
A PIPE SLEEVE THROUGH A FOUNDATION WALL 



2.13 OPENINGS FOR PIPING 

a. Openings for plumbing piping shall be sealed as required to maintain the integrity of the wall, floor, ceiling, 
or roof that has been penetrated. 

b. Collars or escutcheon plates shall be provided to cover the openings around pipes where the piping pen- 
etrates walls, floors, or ceilings in finished areas that are exposed to view. 



2.14 USED MATERIAL OR EQUIPMENT 

Used plumbing material or equipment that does not conform to the standards and regulations set forth in this 
Code shall not be installed in any plumbing system. 

2.15 CONDEMNED EQUIPMENT 

Any plumbing equipment condemned by the Authority Having Jurisdiction because of wear, damage, defects or 
sanitary hazards, shall not be used for plumbing purposes. 



76 



2006 National Standard Plumbing Code-Illustrated 



2.16 FREEZING OR OVERHEATING 

a. The plumbing system shall be protected from freezing or overheating. The following conditions shall be met: 

1 . Water service piping shall be installed below recorded frost lines. Minimum earth cover shall be 

inches. 

2. Minimum earth cover for building sewers that connect to public sewage systems shall be inches. 



inches. 



Minimum earth cover for building sewers that connect to individual sewage disposal systems shall be_ 

3. In systems that are used seasonally, water piping shall be installed to be drained. 

4. Piping shall be installed so that the contents will not be heated due to close proximity to any heat source or 
from direct solar radiation. 

5. In areas with seasonal freezing temperatures, all waste and water supply piping in exterior walls and other 
areas shall be protected from freezing. 

See Figure 2.16 



FINISHED GRADE 



X INCHES 




DISTANCES X AND Y ARE 
GROUND COVER, NOT 
TRENCH DEPTH 



NOTES: 

1 . Refer to the adopting ordinance for this Plumbing Code to determine the minimum required coverfor 
water service and sewer piping. 

2. Locating piping in exterior walls where freezing is possible should be avoided if possible. Thermal 
insulation only retards the loss of heat, it does not prevent it. 

3. Heat tracing may be required where piping is exposed outdoors or in unheated spaces. 

Figure 2.16 
DEPTH OF COVER FOR WATER SERVICE AND SEWER PIPING 



2.17 PROTECTING FOOTINGS 

Trenching parallel to and below the bottom of footings or walls shall not penetrate a 45° plane extending outward 
from the bottom corner of the footing or wall, unless the soil type is approved by the Authority Having Jurisdiction 
for a different angle of repose. See Figure 2.17 



2006 National Standard Plumbing Code-Illustrated 



77 



BUILDING WALL, 
COLUMN, OR 
OTHER STRUCTURAL 
MEMBER ■ 



EXCAVATION 




SOIL TYPE AND CONDITION 
MAY PERMIT OR REQUIRE A 
DIFFERENT ANGLE OF REPOSE 



NOTES: 

1 . Check the project design documents to verify that a 45 degree angle of repose is permissible. 

2. Consult the project structural engineer if conditions dictate that excavations must be closer 
than 45 degrees from the bottom edge of footings. 

Figure 2.17 
PROTECTING STRUCTURAL FOOTINGS FROM BEING UNDERMINED 

2.18 CONNECTIONS TO PLUMBING SYSTEMS REQUIRED 

Every plumbing fixture, drain, appliance, or appurtenance thereto that is to receive or discharge any liquid waste or 
sewage shall discharge to the sanitary drainage system of the building in accordance with the requirements of this 
Code. 

2.19 CONNECTION TO WATER AND SEWER SYSTEMS 

2.19.1 Availability ofPublic Water and Sewer 

The water distribution and drainage systems of any building in which plumbing fixtures are installed shall be 
connected to a public water supply and sewer system respectively if the public water supply and/or public 
sewer is within feet of any property line of the premises, or other reasonable distance as determined 



by the Authority Having Jurisdiction. See Figure 2.19.1 



PUBLIC SEWER 









PUBLIC WATER SUPPLY 



NOTES: 

1 . Refer to the adopting ordinance for this Plumbing Code to determine the distance from which 
properties must be connected to public water and sewer systems. 

2. Connections to public water and sewer systems are more desirable than private systems, from the 
standpoint of public health and convenience. 

Figure 2.19.1 
REQUIRED CONNECTION OF PROPERTIES TO PUBLIC WATER AND SEWER SYSTEMS 



78 



2006 National Standard Plumbing Code-Illustrated 



2.19.2 Private Systems 

Where either a public water supply or sewer system, or both, are not available, a private individual water 
supply or individual sewage disposal system, or both, shall be provided, and the water distribution system and 
drainage system shall be connected thereto. Such private systems shall meet the standards for installation and 
use established by the Health Department or other agency having jurisdiction. (See Chapters 16 and 17.) See 
Figure 2.19.1. Also the definitions of "Private Sewage Disposal System" and "Private Water 
Supply". 



Comment: Plumbing in buildings connected to private water or sewage systems must comply with all 
applicable requirements of this Code or the Authority Having Jurisdiction. 



2.20 WASHROOM & TOILET ROOM REQUIREMENTS 

2.20.1 Light and Ventilation 

Light and ventilation shall be provided as required by other applicable codes. 

2.20.2 Location of Piping and Fixtures 

Piping, fixtures, or equipment shall not be located in such a manner as to interfere with the normal operation 
of windows, doors, or other exit openings. 

2.21 PIPING MEASUREMENTS 

Except where otherwise specified in this Code, all measurements shall be made to the center lines of the pipes. 

2.22 WATER CLOSET CONNECTIONS 

a.Three-inch bends may be used on water closets or similar connections provided a 4-inch by 3-inch flange is 
installed to receive the closet fixture horn, 
b. Four-inch by three-inch closet bends shall be permitted. 
See Figures 2.22 





-- 4" NOM. -» 




N k^s 




k\N M 


™^ 


\ A 


f 




\ ! 






- 3" NOM. - 





FINISHED FLOOR 




3" NOM. 



NOTES: 

1 . Reducing fixture drains for water closets from 4" to 3" is permissible. 

Figure 2.22 
WATER CLOSET DRAIN CONNECTIONS 



2006 National Standard Plumbing Code-Illustrated 



79 



2.23 DEAD ENDS 

a. In the installation or removal of any part of a drainage or vent system, dead ends shall be avoided. 
EXCEPTION: Where necessary to extend a cleanout so as to be accessible. 

b. In the installation or removal of any part of a potable water system, dead ends shall be avoided See 
Figure 2.23 and the definition of "Dead End". 



Comment: Rough-ins for future fixtures are not considered dead ends if the piping is accessible and can 
be cleared of any blockages when the future fixtures are installed. 



2.24 TOILET FACILITIES FOR CONSTRUCTION WORKERS 

Suitable toilet facilities shall be provided and maintained in a sanitary condition for the use by workers during 
construction. Non-sewer type toilet facilities for construction workers shall conform to ANSI Z4.3. 

2.25 FOOD HANDLING AREAS 

a. Food or drink shall not be stored, prepared or displayed beneath overhead sewer or drain pipes unless such pipes 
are protected against leakage or condensation reaching the food or drink as described below for new construction. 
In newly constructed or remodeled establishments, soil or drain pipes located over food preparation, storage, 
display or serving areas are undesirable. Where building design requires that soil or drain pipes be located over 
such areas, the installation shall be made with the least possible number of joints and shall be installed so as to 
connect to a vertical stack at the nearest wall or vertical building support and the construction shall be performed 
as follows: 

1. All openings through floors over such areas shall be provided with sleeves securely bonded to the floor 
construction and projecting not less than 3/4 inch above top of the finished floor with space between sleeve and 
pipe or duct sealed. 

2. Floor and shower drains installed above such areas shall be equipped with integral seepage pans. 

3. Plumbing fixtures in rooms located above such areas shall be of the wall mounted type except bathtubs. Tubs 
shall have waste and overflow connections made above floor and piped to the trap below the floor. Connections 
through floors and traps shall conform with all other provisions of this regulation. No floor openings, other than 
sleeve for waste pipe, will be permitted for tubs. 

4. All other soil or drain pipes shall be of an approved material as listed in Table 3.1.3 and Section 11.1. All 
materials shall conform to established standards. Cleanouts shall be extended through the floor construction above. 

5. Soil and drain pipes located above such areas shall be subjected to a standing water test of not less than 25 
feet. 

6. Piping subject to operation at temperatures that will form condensation on the exterior of the pipe shall be 
thermally insulated. 

7. Where pipes are installed in ceilings above such areas, the ceiling shall be of the removable type, or shall be 
provided with access panels in order to form a ready access for inspection of piping. 

8. In lieu of the above, any other method may be approved by the Authority Having Jurisdiction that does not 
conflict with applicable health codes. 

9. The installation of vacuum collection systems in buildings where food is prepared, stored or displayed shall be 
permitted provided that the system is under constant vacuum. The piping shall be smooth bore and long pattern 
fittings shall be used. Bracing shall be in accordance with the manufacturer's instructions. 

10. Floor sinks in food handling areas shall be of the sanitary design with smooth, corrosion-resistant interior 
surfaces that can be readily cleaned. 

See Figures 2.25 - A and 2.25 - B 



"" 2006 National Standard Plumbing Code-Illustrated 




FILLER MATERIAL - WATERTIGHT 
AND SEALED ACCORDING TO 
FIRE AND BUILDING CODES 

NOT LESS THAN 
3/4" ABOVE FLOOR 



LO 



NOTES: 

1 . The 3/4" extended sleeve prevents spillage on the floor above from leaking down into the food 
handling area and contaminating the food products. 



Figure 2.25 - A 
A PIPE PENETRATION OF A FLOOR ABOVE A FOOD HANDLING AREA 



BATHTUB 



WASTE & OVERFLOW 
ABOVE FLOOR 






WATER SUPPLY NOT SHOWN 



V7* 



WALL HUNG 
WATER CLOSET 

3 



LAVATORY 




SEE FIGURE 2.25A 



PIPING IS IN CEILING SPACE 
PIPING MUST BE ACCESSIBLE 

NOTES: 

1 . All pipe penetrations through the floor above must have extended pipe sleeves. See Figure 2.25 - A. 
The number of floor penetrations should be minimized. 

2. Floor -outlet water closets are not permitted above a food handling area. 

3. Bathtubs and showers must have above-the-floor waste outlets with piping extended to a point 
where an extended pipe sleeve can be installed. 

4. Piping run in a ceiling space above a food handling area must be fully accessible. 

Figure 2.25 - B 
PLUMBING FIXTURES ABOVE A FOOD HANDLING AREA 



2006 National Standard Plumbing Code-Illustrated 



81 



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Materials 



3.1 MATERIALS 

3.1.1 Minimum Standards 

The standards cited in this chapter shall control all materials, systems, and equipment used in the construction, 
installation, alteration, repair, or replacement of plumbing or drainage systems or parts thereof. 
EXCEPTIONS: 

(1) The Authority Having Jurisdiction shall allow the extension, addition to or relocation of existing water, 
soil, waste, drainage and vent pipes with materials of like grade or quality as permitted in Section 3.12.2. 

(2) Materials not covered by the standards cited in this chapter may be used with the approval of the 
Authority Having Jurisdiction as permitted in Section 3. 12.2. 

3.1.2 General Requirements 

a. Materials, fixtures, or equipment used in the installation, repair or alteration of any plumbing system 
shall conform at least to the standards listed in this chapter, except as otherwise approved by the Authority 
Having Jurisdiction under the authority contained in Section 3.12. 

b. Materials installed in plumbing systems shall be so handled and installed as to avoid damage so that the 
quality of the material will not be impaired. 

c. No defective or damaged materials, equipment or apparatus shall be installed or maintained. (See 
Sections 2.14 and 2.15) 

d. All materials used shall be installed in strict accordance with the standards under which the materials 
are accepted and approved, including the appendices of the standards, and in strict accordance with the 
manufacturer's instructions. Where the provisions of material standards or manufacturer's instructions 
conflict with the requirements of this Code, this Code shall prevail. 

3.1.3 Standards Applicable to Plumbing Materials 

A material shall be considered approved if it meets one or more of the standards cited in Table 3.1.3, and in the 
case of plastic pipe, also the listed standard of the NSF International. Materials not listed in Table 3. 1 .3 shall be 
used only as provided for in Section 3.12.2 or as permitted elsewhere in this Code. 

Note: Abbreviations in Table 3.1.3 refer to the following organizations: 



AHAM Association of Home Appliance Manufacturers 
1 1 1 1 1 9th Street, NW - Suite 402 
Washington, DC 20036 USA 
tel: 1-202-872-5955 
fax:1-202-872-9354 



2006 National Standard Plumbing Code-Illustrated 



83 



ANSI American National Standards Institute 

25 West 43rd Street - 4th Floor 
New York, NY 10036 USA 
tel: 1-212-642-4900 
fax:1-212-398-0023 

ASME ASME International 
Three Park Avenue 
New York, NY 10016-5990 USA 
tel: 1-800-843-2763 
fax:1-212-591-7674 

ASSE ASSE International 

901 Canterbury Road - Suite A 
Westlake, OH 44145 USA 
tel: 1-440-835-3040 
fax:1-440-835-3488 

ASTM ASTM International 

100 Barr Harbor Drive - PO Box C700 

West Conshohocken, PA 1 9428-2959 

USA 

tel: 1-610-832-9585 

fax: 1-610-832-9555 

AWWA American Water Works Association 
6666 W. Quincy Avenue 
Denver, CO 80235 USA 
tel: 1-800-926-7337 
fax: 1-303-347-0804 

CISPI Cast Iron Soil Pipe Institute 

5959 Shallowford Road - Suite 41 9 
Chattanooga, TN 37421 USA 
tel: 1-423-892-0137 
fax:1-423-892-0817 

CSA Canadian Standards Association 

5060 Spectrum Way 
Mississauga, ON L4W 5N6 
CANADA 
tel: 1-800-463-6727 
fax:1-416-747-2473 

FM FM Global 

1301 Atwood Avenue - PO Box 7500 
Johnston, RI 02919 USA 
tel: 1-401-275-3000 
fax:1-401-275-3029 



I APMO International Association of 

Plumbing and Mechanical Officials 
5001 E.Philadelphia Street 
Ontario, C A 91761 USA 
tel: 1-909-472-4100 
fax:1-909-472-4150 

ISEA International Safety Equipment 

Association 
1901 N. Moore Street 
Arlington, VA 22209-1762 USA 
tel: 703-525-1695 
fax:703-528-2148 

MSS Manufacturers Standardization Society 

127 Park Street NE 
Vienna, VA 22180 USA 
tel: 1-703-281-6613 
fax:1-703-281-6671 

NFPA National Fire Protection Association 
1 Batterymarch Park 
Quincy, MA 02169-7471 USA 
tel: 1-617-770-3000 
fax:1-617-770-0700 

NSF NSF International 

789 N. Dixboro Road 

Ann Arbor, MI 48113-0140 USA 

tel: 1-800-673-6275 

fax: 1-734-769-0109 

PDI Plumbing & Drainage Institute 

800 Turnpike Street - Suite 300 
North Andover, MA 01845 USA 
tel: 1-800-589-8956 
fax:1-978-557-0721 

UL Underwriters Laboratories Inc. 

333 Pfmgsten Road 
Northbrook, IL 60062-2096 USA 
tel: 1-847-272-8800 
fax:1-847-272-8129 



84 



2006 National Standard Plumbing Code-Illustrated 



3.1.4 Identification of Materials 

Materials shall be identified as provided in the standard to which they conform. 

3.2 SPECIAL MATERIALS 

3.2.1 Miscellaneous Materials 

Sheet and tubular copper and brass for the following uses shall be not less than: 

a. General use - 12 oz. per square foot 

b. Flashing for vent pipes - 8 oz. per square foot 

c. Fixture traps and trap arms - 17 gauge or ASME Al 18.2/CSA B125.2 

d. Fixture tailpieces - 20 gauge or ASME Al 18.2/CSA B125.2 

e. Tailpieces with dishwasher connections - 20 gauge or ASME Al 18.2/CSA B125.2 

f. Continuous wastes - 20 gauge or ASME Al 18.2/CSA B 125.2 

3.2.2 Lead 

See Table 3.1.3. Sheet lead shall be not less than the following: 

a. Shower pans — not less than 4 pounds per square foot (psf) and be coated with an asphalt paint or 
equivalent. 

b. Flashings of vent terminals — not less than 3 pounds per square foot (psf). 

c. Lead bends and lead traps shall not be less than 1/8" wall thickness. 

3.2.3 Plastic 

a. Trap and tailpiece fittings — minimum 0.062" wall thickness. 

b. Piping — see specific application — Sections 3.4 to 3.1 1. 

c. Shower pans — approved plastic sheeting material. 



Comment: Plastic shower pans should not be covered with asphalt unless recommended by the manu- 
facturer. 



3.3 FITTINGS, FIXTURES, APPLIANCES & APPURTENANCES 

3.3.1 Drainage Fittings 

See Sections 2.3 and 2.4 for fittings and connections in drainage systems. 

3.3.2 Cleanout Plugs and Caps 

a. Cleanout plugs shall be of brass, plastic, stainless steel, or other approved materials and shall have 
raised or countersunk square heads, except that where raised heads will cause a tripping hazard, countersunk 
heads shall be used. 

b. Cleanout caps shall be of brass, plastic, reinforced neoprene, cast-iron, or other approved material and 
shall be readily removable. 

See Figure 3.3.2 



2006 National Standard Plumbing Code-Illustrated 85 



(1 




COUNTERSUNK HEAD PLUG 



RAISED HEAD PLUG 



Figure 3.3.2 
CLEANOUT PLUGS 



3.3.3 Fixtures 

a. Plumbing fixtures shall be constructed from approved materials having smooth, non-absorbent surfaces 
and be free from defects, and except as permitted elsewhere in this Code, shall conform to the standards 
cited in Table 3.1.3. 

b. Materials for special use fixtures not otherwise covered in this Code shall be constructed of materials 
especially suited to the use for which the fixture is intended. 

See Chapter 7 for the requirements for specific fixtures 



Comment #1: The standards for plumbing fixtures that are listed in Table 3.1.3 reflect consensus 
agreement between manufacturers, industry representatives, and consumer groups. 

Comment #2: Slip resisting surfaces in bathtubs and showers do not constitute a violation of the require- 
ment for smooth surfaces. 



3.3.4 Floor Flanges and Mounting Bolts 

a. Floor flanges for water closets or similar fixtures shall be not less than 1/8" thick for brass, 1/4" thick 
and not less than 1-1/2" caulking depth for cast-iron or galvanized malleable iron. Approved copper and plastic 
flanges may be used. 

b. If of hard lead, they shall weigh not less than 1 lb. 9 oz. and be composed of lead alloy with not less 
than 7.75 percent antimony by weight. Flanges shall be soldered to lead bends or shall be caulked, soldered, or 
threaded into other metal. 

c. Closet screws and bolts shall be corrosion-resisting. 

d. Connections between drainage piping and floor outlet water closets shall be made by means of an 
approved flange that is attached to the drainage piping in accordance with the provisions of this chapter. The 
floor flange shall be set on and securely anchored to the finished floor. 

3.3.5 Flush Pipes and Fittings 

Flush pipes and fittings shall be of nonferrous material. When of brass or copper tube, the material shall be at 
least 0.0313" in thickness (No. 20 U.S. gauge). 

3.3.6 Reserved 

3.3.7 Interceptors 

Interceptors shall meet the requirements of Chapter 6. 



86 



2006 National Standard Plumbing Code-Illustrated 



3.3.8 Pressure Tanks and Vessels 

, c a " ?t W f f ' t0rage tanks sha11 meet construction requirements of ASME, AGA or UL as appropriate. 

(oee [able 3.1.3) 

b. Storage tanks less in volume than those requirements specified by ASME shall be of durable materials 
and constructed to withstand 125 p.s.i. with a safety factor of 2. 

3.3.9 RoofDrains 

Roof drains shall be of cast-iron, copper, lead, or other approved corrosion-resisting materials. See Section 

3.3.10 Safety Devices for Pressure Tanks 

Safety devices shall meet the requirements of the American National Standards Institute, American Society 
of Mechanical Engineers, or the Underwriters Laboratories. Listing by Underwriters Laboratories, American 
Gas Association or National Board of Boiler and Pressure Vessel Inspectors shall constitute evidence of 
conformance with these standards. Where a device is not listed by any of these, it shall have certification by 
an approved laboratory as having met these requirements. (See Section 10.16.) 

3.3.11 Septic Tanks 

a. Plans for all septic tanks shall be submitted to the Authority Having Jurisdiction for approval Such plans 
shall show all dimensions, reinforcing, structural calculations and such other pertinent data as may be re- 
quired. 

b. Septic tanks shall be constructed of sound durable materials, not subject to excessive corrosion or decay 
and shall be watertight. (See Sections 16.6.5 and 16.6.6.) 

3.3.12 Carriers and Supports 

Carriers and supports for plumbing fixtures shall comply with ASME Al 1 2.6. 1, ASME Al 12.6.2 or ASME 
/\ l iz, l y. iz. 

3.4 POTABLE WATER PIPING 

3.4.1 Plastic Piping 

Plastic piping materials used for the conveyance of potable water shall comply with NSF 14 and be marked 
accordingly. 

3.4.2 Water Service Piping 

Water service piping to the point of entrance into the building shall be of materials listed in Table 3 4 and shall 
be water pressure rated not less than 160 psi at 73°F. See Table 3.4.2. 



Comment: The manufacturer's markings on plastic water service pipe must indicate that it is suitable fo 
160psig@73°F. J 



3.4.3 WaterDistributionPiping 

Water piping for the distribution of hot or cold water within buildings shall be of materials listed in Table 3 4 
and shall be water pressure rated for not less than 100 psi at 180°F. Plastic piping used for hot water distribu- 
tion shall be installed in accordance with the requirements of Section 10.15.8. 



2006 National Standard Plumbing Code-Illustrated 

o7 



NOTE: The working pressure rating for certain approved plastic piping materials varies depending on pipe 
size, pipe schedule and methods of joining. See Table 3.4.3. 

3.4.4 Fittings 

Fittings for water supply piping shall be compatible with the pipe material used. 

3.4.5 Material Ratings and Installation 

a. Piping used for domestic water shall be suitable for the maximum temperature, pressure, and velocity 
that may be encountered, including temporary increases and surges. 

b. Relief valve temperature and pressure relief settings shall not exceed the approved standard rating for 
hot and cold water distribution piping. 

c. Pipe and fittings shall be installed in accordance with the manufacturer's installation instructions and the 
applicable material standards, recognizing any limitations in use. 



Comment: Refer to the standards listed in Table 3.1.3 to determine the pressure and temperature ratings 
of the various piping materials. ____ 



3.4.6 Limit on Lead Content 

a. Materials used in the potable water supply system, including faucets and valves, shall not contain more 
than 8 percent lead. 

b. Drinking water system components shall comply with the lead leachate requirements as specified for 
covered products of NSF International 61. 

See Section 4.2.4 for the limit on lead in solder filler metal 



Comment: The limit of 8% lead is based on the EPA Safe Drinking Water Act. Generally, fixture fitting 
castings do not exceed 7% lead. ____ 



3.5 SANITARY DRAINAGE PIPING 

3.5.1 Aboveground Piping - Soil, Waste and Indirect Waste 

Aboveground soil and waste piping within buildings shall be of materials listed in Table 3.5. 

3.5.2 Underground Building Sanitary Drains 

Underground building drains and other underground sanitary drain and waste piping within buildings shall be of 
materials listed in Table 3.5. 

3.5.3 Building Sanitary Sewer 

Sanitary sewer piping outside of buildings shall be of materials listed in Table 3.5. Joints shall be watertight 
and root proof. 

3.5.4 Plastic Piping 

a. Pipe and fittings classified by standard dimension ratio that are underground outside of buildings shall be 
SDR 35 or heavier (lower SDR number). Pipe and fittings within buildings shall be SDR 26 or heavier (lower 

SDR number). 

b. Pipe and fittings classified by pipe stiffness that are underground outside of the buildings shall be PS-45 
or heavier (higher PS number). Pipe and fittings within buildings shall be PS- 1 00 minimum. 



gg 2006 National Standard Plumbing Code-Illustrated 



3.5.5 Vitrified Clay Pipe 

Vitrified clay pipe shall be joined using compression joints or couplings. Vitrified clay pipe installed under- 
ground within buildings shall be extra strength and shall have 12" minimum earth cover. 

3.5.6 Fittings 

Fittings in drainage systems shall be compatible with the pipe used and shall have no ledges, shoulders, or 
reductions that can retard or obstruct flow. Threaded fittings shall be the recessed drainage type. 

3.6 VENT PIPING 

3.6.1 Abo veground Piping 

Aboveground vent piping in buildings serving sanitary, waste, or storm drainage systems shall be of materials 
listed in Table 3.6. 

3.6.2 Underground Piping 

Vent piping installed underground shall be of materials listed in Table 3.6. 

3.6.3 Plastic Piping 

a. Pipe and fittings classified by standard dimension ratio that are underground outside of buildings shall be 
SDR 35 or heavier (lower SDR number). Pipe and fittings within buildings shall be SDR 26 or heavier (lower 
SDR number). 

b. Pipe and fittings classified by pipe stiffness that are underground outside of buildings shall be PS-45 or 
heavier (higher PS number). Pipe and fittings within buildings shall be PS- 100 minimum. 

3.6.4 Fittings 

Fittings in vent piping shall be compatible with the pipe material used. Where threaded pipe is used, fittings 
shall be either the drainage or pressure type, galvanized or black. 

3.7 STORM DRAINAGE PIPING 

3.7.1 Exterior Gutters and Leaders 

Exterior gutters and rain leaders shall be of galvanized sheet metal, aluminum, plastic or other approved 
material. 

3.7.2 Interior Conductors 

Stormwater drain piping installed aboveground in buildings shall be of materials listed in Table 3 .7. 

3.7.3 Underground Building Storm Drains 

Underground building storm drains and other underground stormwater piping within buildings shall be of 
materials listed in Table 3.7. 

3.7.4 Building Storm Sewer 

Building storm sewer piping outside ofbuildings shall be of materials listed in Table 3.7. 



2006 National Standard Plumbing Code-Illustrated 89 



3.7.5 Plastic Piping 

a. Pipe and fittings classified by standard dimension ratio that are underground outside of buildings shall be 
SDR 35 or heavier (lower SDR number). Pipe and fittings within buildings shall be SDR 26 or heavier (lower 
SDR number), except that SDR 35 fittings shall be permitted. 

b. Pipe and fittings classified by pipe stiffness that are underground outside of buildings shall be PS-45 or 
heavier (higher PS number). Pipe and fittings within buildings shall be PS- 1 00 minimum. 

3.7.6 Vitrified Clay Pipe 

Vitrified clay pipe shall be joined using compression joints or couplings. Vitrified clay pipe installed under- 
ground within buildings shall be extra strength and shall have 12" minimum earth cover. 

3.7.7 Fittings 

Fittings in drainage systems shall be compatible with the pipe used and shall have no ledges, shoulders, or 
reductions that can retard or obstruct flow. Threaded fittings shall be the recessed drainage type. 

3.8 FOUNDATION DRAINS AND SUBSOIL DRAINAGE 

Piping for foundation drains and other subsoil drainage shall be of materials listed in Table 3.8. 

3.9 AIR CONDITIONING CONDENSATE DRAIN PIPING 

Indirect waste piping from air conditioning unit drains to the point of disposal shall be of a material approved for 
either potable water, sanitary drainage or storm drainage. 

3.10 CONDENSATE DRAINS FROM COMBUSTION PROCESSES 

Piping used to convey condensate from combustion processes (such as from flues and chimneys) shall conform to 
the equipment manufacturer's instructions. 

3.11 CHEMICAL AND SPECIAL WASTE SYSTEMS 

3.11.1 Drain Piping 

Separate drainage systems for chemical wastes shall be of corrosion resistant material approved by the 
Authority Having Jurisdiction. Materials acceptable for chemical waste drainage systems include chemically 
resistant glass pipe, high silicon content cast-iron pipe, vitrified clay pipe, plastic pipe, plastic lined pipe, Type 
316L stainless steel DWV pipe, and lead pipe. 

3.11.2 Vent Piping 

Vent piping on chemical waste systems shall conform to that required for chemical waste pipe except as may 
be otherwise authorized by the Authority Having Jurisdiction, and shall be installed independently through the 
roof. 

3.12 ALTERNATE MATERIALS AND METHODS 

3.12.1 Existing Buildings 

a. Plumbing work performed in existing buildings shall conform to the requirements of this Code, unless 
the Authority Having Jurisdiction finds that such conformance would result in an undue hardship. 

b. The Authority Having Jurisdiction may grant a variation to the extent necessary to relieve the undue 
nature of the hardship. 

c. A record, open to the public, shall be kept of each variation granted under this section. 



90 



2006 National Standard Plumbing Code-Illustrated 



3.12.2 Approval 

a. The Authority Having Jurisdiction may approve the use of any material or method not expressly con- 
forming to the requirements of this Code provided all of the following conditions are met: 

1 . The material or method is not expressly prohibited by this Code. 

2. The material or method is determined to be of such design or quality as to appear suitable for the 
proposed use. 

3. A record of such approval is kept and shall be available to the public. 

3.12.3 Tests 

When there is insufficient evidence to verify claims for alternate materials, the Authority Having Jurisdiction 
may require tests of compliance as proof of suitability. Such tests shall be made by an approved testing 
agency at the expense of the applicant. 

3.12.4 Test Procedure 

Tests shall be made in accordance with approved standards; but in the absence of such standards, the Au- 
thority Having Jurisdiction shall specify the test procedure. 

3.12.5 Repeated Tests 

The Authority Having Jurisdiction may require tests to be repeated if, at any time, there is reason to believe 
that an alternate material no longer conforms to the requirements on which its approval was based. 



2006 National Standard Plumbing Code-Illustrated 91 



Table 3.1.3 
STANDARDS FOR APPROVED PLUMBING MATERIALS AND EQUIPMENT 





1 


Hub & Spigot Cast-iron Soil Pipe and Fittings: 


ASTMA74-05. 


2 


Hubless Cast- Iron Soil Pipe and Fittings: 


CISPI 301-05, ASTM A888-05. 


3 


Ductile-Iron Pressure Pipe: 


ASTMA377-03, AWWAC151/A21.51-02. 


4 


Ductile-Iron and Gray-Iron Fittings (3" and larger): 


AWWAC110/A21.10-03. 


5 


Cement-Mortar Lining for Ductile-Iron Pipe and Fittings: 


AWVVA C104/A21.4-03. 


6 


Steel Pipe, Galvanized, Welded and Seamless: 


ASTM A53/A53M-04a, ASME B36.I M- 
2004 


7 


Cast-iron Threaded Drainage Fittings: 


ASMEB16.12-1998. 


8 


Cast-iron Threaded Fittings, Classes 1 25 and 250: 


ASME B16.4-1 998. 


9 


Malleable-Iron Threaded Fittings, Class 1 50 and 300: 


ASMEB16.3-1998. 


10 


Ferrous Pipe Plugs, Bushings, and Locknuts with Pipe Threads: 


ASMEB16.14-1991. 


11 


Stainless Steel DWV Pipe and Fittings, Types 304 and 3 16L (3) 


ASMEAU2.3.1-1993 




If. NON-FERROUS M ETALLIC PIPE AND FITT1 NGS 


1 


Brass Pipe, Red, Seamless, Standard Sizes: 


ASTMB43-98(R2004). 


2 


Cast Bronze Threaded Fittings, Classes 125 & 250: 


ASME B16.15-1985 (R2004). 


3 


Cast Copper Alloy Pipe Flanges, Class 1 50, 300, 400, 600, 900, 1 500, 
2500, and Flanged Fittings, Classes 150 and 300: 


ASMEB16.24.2001. 


4 


Cast Copper Alloy Solder Joint Drainage Fittings - DWV: 


ASMEB16.23-2002. 


5 


Cast Copper Alloy Solder Joint Pressure Fittings: 


ASMEB16.18-2001. 


6 


Copper Drainage Tube (DWV): 


ASTMB306-02. 


7 


Copper Pipe, Seamless, Standard Sizes: 


ASTMB42-02.el 


8 


Copper Pipe, Threadless (TP): 


ASTMB302-02. 


9 


Copper Water Tube, Seamless (K, L, M): 


ASTMB88-03. 


10 


Grooved & Shouldered Joints (split couplings, for copper tube): 


AWWAC606-04. 


11 


Wrought Copper and Wrought Copper Alloy Solder Joint Drainage 
Fittings-DWV: 


ASME Bl 6.29-2001. 


12 


Wrought Copper and Copper Alloy Solder Joint Pressure Fittings: 


ASMEB16.22-2001. 


13 


Reserved 




14 


Reserved 




15 


Cast Copper Alloy Fittings for Flared Copper Tubes: 


ASME Bl 6.26-1 998. 


16 


Wrought Copper and Copper Alloy Braze- Joint Pressure Fittings: 


ASME Bl 6.50.2001. 



92 



2006 National Standard Plumbing Code-Illustrated 



III. NON-METALLIC PIPE AND FITTINGS ' 


1 


Acrylonitrile-Butadiene-Styrene (ABS) Plastic Pipe (SDR-PR) (1/8"- 12")- 


ASTMD2282-(2005) 


2 


Acrylonitrile-Butadiene-Styrene (ABS) Plastic Pipe, Schedules 
40and80(l/8"-12"): 


ASTMD1527-99el. 


3 


Reserved 




4 


Acrylonitrile-Butadiene-Styrene (ABS) Schedule 40 Plastic Drain, 
Waste, and Vent Pipe and Fittings (1-1/4"- 6"): 


ASTMD2661-02. 


5 
6 


Acrylonitrile-Butadiene-Styrene (ABS) Schedule 40 Plastic 
Drain, Waste, and Vent Pipe With a Cellular Core (1 - 1/4"- 6"): 


ASTMF628-01. 


Acrylonitrile-Butadiene-Styrene (ABS) Sewer Pipe andfittings (3"- 1 2")- 


ASTMD2751-05. 


7 


Acrylonitrile-Butadiene-Styrene (ABS) and Poly (Vinyl Chloride) (P VC) 
Composite Sewer Pipe (6"- 15"): 


ASTMD2680-01. 


8 


Poly (Vinyl Chloride) (PVC) Pressure Pipe for Water (4"- 1 2"): 


AWWAC900-97 


9 


Poly (Vinyl Chloride) (PVC) Plastic Pipe, Schedules 40, 80, and 
120(l/8"-24"): 


ASTMD1785-05. 


10 


Poly (Vinyl Chloride) (PVC) Plastic Pipe Fittings, Schedule40; 
socket-type(l/8"-8"): 


ASTMD2466-05. 


11 


Poly (Vmyl Chloride) (PVC) Plastic Pipe Fittings, Schedule 80; 
socket-type (1/8"- 8"): 


ASTMD2467-04el. 


12 


Poly (Vinyl Chloride) (PVC) Plastic Pipe Fittings, Schedule 80, 
Threaded (1/8"- 6"): 


ASTMD2464-99el. 


13 


Poly (Vinyl Chloride) (PVC) Pressure-Rated Pipe, (SDR Series) (1 /8"- 36")- 


ASTMD224I-04b. 


14 


Poly (Vinyl Chloride) (PVC) Plastic Drain, Waste, and Vent 
PipeandFittings(l-l/4"- 12"): 


ASTMD2665-04ael. 


15 


Poly (Vinyl Chloride) ( PVC) Schedule 40 Drainage and D WV 
Fabricated Fittings: 


ASTMF1 866-05. 


16 


3.25" Outside Diameter Poly (Vinyl Chloride) (PVC) 
Plastic Drain, Waste, and Vent Pipe and Fittings: 


ASTMD2949-01ael. 


17 


Poly (Vinyl Chloride) (PVC) Sewer Pipe and Fittings (2"-6"): 


ASTMD2729-03. 


18 


Poly (Vinyl Chloride) (PVC) Gasketed Sewer Fittings (4"-27"): 


ASTMF1336-02. 


19 


Coextruded Poly (Vinyl Chloride) (PVC) Plastic Pipe with a 
Cellular Core; Non-Pressure Uses, IPS Schedule 40 ( 1 - 1 /4"- 12")- 


ASTMF891-04. 


20 


Coextruded Poly (Vinyl Chloride) (PVC) Plastic Pipe with a Cellular Core; 
Non-Pressure Uses, PS and Sewer/Drain Series (2"- 18"): 


ASTMF891-04. 


21 


Reserved 




22 


Type PSM Poly (Vinyl Chloride) (PVC) Sewer Pipe and Fittings (4"- 15")- 


ASTMD3034-04a. 


23 


Chlori nated Poly (Vinyl Chloride) (CPVC) Plastic Hot- and Cold-Water 
Distribution Systems (3/8"- 2"): 


ASTMD2846-99el. 


24 


Chlorinated Poly (Vinyl Chloride) (CPVC) Plastic Pipe (SDR-PR) (1/4"- 1 2")- 


ASTM F442-99. 


25 


Chlorinated Poly (Vinyl Chloride) (CPVC) Plastic Pipe, Schedules 40 
and 80 (1/4"- 12"): 


ASTMF441-02. 


26 


Chlorinated Poly (Vinyl Chloride) (CPVC) Plastic Pipe Fittings, Schedule 
80;Socket-type(l/4"-8"): 


ASTMF439-02el. 


27 


Chlorinated Poly (Vinyl Chloride) (CPVC) Plastic Pipe Fittings, Schedule 80 
Threaded (1/4"- 6"): 


ASTMF437-99. 


28 


Polyethylene (PE) Pressure Pipe and Tubing for Water Service (1/2"- 3"): 


AWWAC901-02. 




— - _| 



2006 National Standard Plumbing Code-Illustrated 



93 



29 Polyethylene (PE) Plastic Pipe (SDR-PR) Based on Controlled Outside 
Diameter(l/2"-6"): 



31 



33 

34 



35 



36 



38 



39 
40 
41 



42 



43 



44 



46 



47 



48 



49 



51 



53 



54 



55 



56 



57 



58 



59 



3 Polyethylene (PE) Plastic Pipe (SIDR-PR) Based on Controlled Inside Diameter 
(1/2"- 6"): 



Reserved 



32 Polyethylene (PE) Plastic Pipe, Schedules 40 and 80, Based on Outside 

Diameter (1/2"- 12"): 

Polyethylene (PE) Plastic Tubing (1/2"- 2"): 



Butt Heat Fusion Polyethylene (PE) Plastic Fittings for Polyethylene (PE) 
Plastic Pipe and Tubing (1/2"- 48"): 



Plastic Insert Fittings for Polyethylene (PE) Plastic Pipe (1/2"- 4"): 



Corrugated Polyethylene (PE) Tubing and Fittings (3"- 6"): 



37 Smoothwall Polyethylene (PE) Pipe for use in Drainage and Waste Disposal 
Absorption Fields (3"- 6"): 



Styrene-Rubber (SR) Plastic Drain Pipe and Fittings (2"- 6"): 



Reserved 



ASTMD3035-03a. 



ASTMD2239-03. 



ASTMD2447-03. 



ASTMD2737-03. 



ASTMD3261-03. 



ASTMD2609-02. 



ASTMF405-97. 



ASTMF810-01. 



ASTM D2852-95(R2002). 



Fiberglass Pressure Pipe ( 1 " and larger): 

Fiberglass (GFR) Sewer and Industrial Pressure Pipe (8" and larger): 



Fiberglass (GFR) Sewer Pipe (8" and larger): 



Fiberglass (GFR) Non-Pressure Pipe Fittings (8" and larger): 



Reserved 



45 Vitrified Clay Pipe, Extra Strength, Standard Strength, and Perforated 
(3" and larger): 



Concrete Drain Tile (4" and larger): 



Concrete Sewer, Storm Drain, and Culvert Pipe; non-reinforced (4" and larger): 



Reinforced Concrete Culvert, Storm Drain, and Sewer Pipe (1 2" and larger): 



Perforated Concrete Pipe (4" and larger): 



50 Crosslinked Polyethylene (PEX) Plastic Hot- and Cold-Water Distribution 

Systems: 



AWWAC950-01. 



ASTMD3754-04. 



ASTMD3262-04. 



ASTMD3840-01. 



ASTM C700-02. 



ASTMC412-03. 



ASTMC14-03. 



ASTMC76-05. 



ASTMC444-03. 



Crosslinked Polyethylene (PEX) Tubing: 



52 Metal Insert Fittings Utilizing a Copper Crimp Ring for SDR9 Crosslinked 
Polyethylene (PEX) Tubing: 



Cold Expansion Fittings with PEX Reinforcing Rings for Use with Cross-linked 
Polyethylene (PEX) Tubing: 



Crosslinked Polyethylene/Aluminum/Crosslinked Polyethylene (PEX- AL-PEX) 
Composite Pressure Pipe (3/8"-!"): 



Polyethylene/Aluminum/Polyethylene (PE-AL-PE) Composite Pressure Pipe 
(3/8"-P) 



Metal Insert Fittings for Crosslinked Polyethylene/Aluminum/Crosslinked 
Polyethylene (PEX-AL-PEX) and Polyethylene/Aluminum/Polyethylene 
Composite Pressure Pipe (PE-AL-PE): 



ASTMF877-05. 



ASTMF876-04. 



ASTMF1807-04. 



ASTM F 1960-05. 



ASTMF1281-03. 



ASTMF1282-03. 



ASTM Fl 974-04. 



Polyethylene/Aluminum/Polyethylene (PE-AL-PE) Composite Pressure Pipe 
Systems ( 1 /4"-l"): 



CrosslinkedPolyethylene/Aluminum/CrosslinkedPolyethylene (PEX-AL-PEX) 
Composite Pressure Pipe Systems (1/4" - 1"): 



Polyethylene (PE) Plastic Pipe (SDR-PR) Based Upon Outside Diameter: 



CSAB1 37.9-02. 



CSA B137.10-02. 



ASTMF714-05.(SeeTables3.4, 
3.5,&3.7forminimumSDR values 
for trenchless replacement systems.) 



94 



2006 National Standard Plumbing Code-Illustrated 



60 


Reserved 




61 


Stainless Steel Clamps for Securing SDR 9 Cross-linked Polyethylene (PEX) 
Tubing to Metal Insert Fittings: 


ASTMF 2098-04. 


62 


CrosslinkedPolyethylene/Aluminum/Crosslinked Polyethylene 
(PEX-AL-PEX) TubingOD Controled SDR-9 (1/2" - 1 "): 


ASTMF2262-04. 


63 


Pressure-rated Composite Pipe and Fittings for Elevated Temperature Service, 
Classes 1 and2(16mm-50mm) 


ASTMF1335-04. 


IV, PIPE JOINTS, JOINING MATERIALS, COUPLINGS, GASKETS 


1 


Pipe Threads, Tapered, General Purpose: 


ASMEB1.20.1-1983(R2001). 


2 


Liquid and Paste Fluxes for Soldering Applications of Copper and Copper 
Alloy Tube: 


ASTMB813-00(el). 


3 


SolderMetal: 


ASTMB32-04. 


4 


BrazingFiller Metal: 


AWSA5.8/A5.8M-2004. 


5 


Pig Lead: 


ASTMB29-03. 


6 


Grooved and Shouldered Joints (Split Couplings): 


AWWAC606-04. 


7 


Flexible Transition Couplings for Underground Piping Systems: 


ASTM CI 173-02. 


8 


Rubber Sheet Gaskets: 


ASTMD1330-04. 


9 


Rubber Gasket Joints for Ductile-Iron and Gray-Iron Pressure Pipe and Fittings: 


ASTMC1173-02;AWWAC111/ 
A21. 11-00. 


10 


Rubber Gaskets for Cast-iron Soil Pipe and Fittings: 


ASTMC564-03a. 


11 


Couplings for Hubless Cast-iron Soil Pipe and Fittings: 


FM 1 680-89, C1SPI 3 1 0-04, ASTM 
C1277-04; ASTM C1540-04. 


12 


Compression Joints for Vitrified Clay Pipe and Fittings: 


ASTMC425-04. 


13 


Rubber Gasket Joints in Circular Concrete Sewer and Culvert Pipe: 


ASTMC443-03. 


14 


Elastomeric Seals (gaskets) for Push-On Joints in Plastic Pipe: 


ASTMF477-02el. 


15 


Flexible Elastomeric Seals for Plastic Pressure Pipe: 


ASTM D3 1 39-98 (R2005). 


16 


Flexible Elastomeric Seals for Plastic Drain and Sewer Pipe: 


ASTM D32 1 2-96a (R2003)el . 


17 


Socket-end IPS PVC Pipe Joints: 


ASTM D2672-96a (R2003). 


18 


Primers for Solvent Cement Joints in PVC Plastic Pipe and Fittings: 


ASTMF656-02. 


19 


Solvent Cement for Acrylonitrile-Butadiene-Styrene (ABS) Plastic Pipe 
and Fittings: 


ASTMD2235-04. 


20 


Solvent Cements for Poly (Vinyl Chloride) (PVC) Plastic Piping Systems: 


ASTMD2564-04. 


21 


Solvent Cements for Transition Joints Between Acrylonitrile-Butadiene-Styrene 
(ABS) and Poly (Vinyl Chloride) (PVC) Non-Pressure Piping Components: 


ASTMD3138-04. 


22 


Solvent Cements for Chlorinated Poly (Vinyl Chloride) (CPVC) Plastic Pipe 
and Fittings: 


ASTMF493-04. 


23 


Solvent Cements for Styrene-Rubber (SR) Plastic Pipe and Fittings: 


ASTM D3 1 22-95(R2002). 


24 


Mechanical Couplings for Drain, Waste and Vent Pipe and Sewer Pipe: 


CSA B602-99 (R2002). 


25 


Fittings for Connecting Water Closets to the Sanitary Drainage System: 


ASME All 2.4.3-1 999 (R2004). 


26 


Standard Specification for Mechanical Couplings Using Thermoplastic 
Elastomeric (TPE) Gaskets for Joining Drain, Waste and Vent (DWV), Sewer, 
Sanitary and Storm Plumbing Systems for Above and Below Ground Use: 


ASTMC1461-02. 


27 


Non-Reinforced Extruded Tee Connections for Piping Applications: 


ASTMF2014-00. 


28 


Standard Specification for Heavy Duty Shielded Couplings Joining Hubless 
Cast Iron Pipe and Fittings 


ATSM CI 540-04. 



2006 National Standard Plumbing Code-Illustrated 



95 



■ V. PLUMBING FIXTURES 


1 


Bathtubs, Plastic: 


IAPMOZ124.1.2-2005;CSA 
B45.5 of CSA B45 Series-02 with 
B45S1-04 Supplement 


2 


Ceramic PlumbingFixtures, Non- Vitreous: 


ASME A112.19.9M-1991 (R2002); 
CSA B45.1 of CSA B45 Series-02 
with B45S1-04 Supplement. 


3 


Drains for Prefabricated and Precast Showers: 


ASME A112.18.2-2005/CSA 
B125.2-05 


4 


Drinking Fountains and Water Coolers, Self Contained, Mechanically 
Refrigerated: 


ARI 1010-2002, 
UL399 Edition 6-1993. 


5 


Enameled Cast-iron Plumbing Fixtures: 


ASMEA112.19.1M-1994(R2004); 
CSA B45.2 of CSA B45 Series-02 
with B45S1-04 Supplement 


6 


Enameled Steel Plumbing Fixtures: 


ASME Al 1 2.1 9.4M- 1 994(R2004); 
CSA B45.3 of CSA B45 Series-02 
with B45S1-04 Supplement 


7 


Floor and Trench Drains: 


ASME Al 12.6.3-2001. 


8 


Lavatories, Plastic: 


ANSI Z124.3-1995; CSA B45.5 of 
CSA B45 Series-02 with B45S1- 
04 Supplement 


9 


Roof, Deck, and Balcony Drains: 


ANSI All 2.6.4-2003. 


10 


Shower Receptors and Shower Stalls, Plastic: 


IAPMOZ1 24.1.2-2005; CSA 
B45.5 of CSA B45 Series-02 with 
B45S1-04 Supplement 


11 


Stainless Steel Plumbing Fixtures (residential design): 


ASME Al 1 2.1 9.3M -1994 (R2004); 
CSA B45.4 of CSA B45 Series-02 
with B45S1-04 Supplement 


12 


Vitreous ChinaPlumbingFixtures: 


ASME Al 12.19.2-2003, CSA 
B45.1 of CSA B45 Series-02 with 
B45S1-04 Supplement 


13 


Water Closet Bowls and Tanks, Plastic: 


ANSI Z124.4-1996; ASME 
A112.19.2-2003; CSA B45.5 of 
CSA B45 Series-02 with B45S1- 
04 Supplement 


14 


Whirlpool Bathtub Appliances: 


ASMEA112.19.7M-1995. 


15 


Reserved 




16 


Urinals, Plastic: 


ANSI Z124.9-1994; CSA B45.5 of 
CSA B45 Series-02 with B45S1- 
04 Supplement 


17 


Fabricated Stainless Steel Security Water Closets: 


IAPMOPS-61-92; CSAB45.4of 
CSA B45 Series-02 with B45S1- 
04 Supplement 


18 


Hydraulic Performance of Water Closets and Urinals: 


ASMEA112.19.2-2003. 


19 


Wall Mounted and Pedestal Mounted Adjustable and Pivoting Lavatory 
and Sink Carrier Systems: 


ASMEA112.19.12-2000(R2004) 



96 



2006 National Standard Plumbing Code-Illustrated 



20 


Plastic Sinks: 


ANSI Z124.6-1997; CSA B45.5 of 
CSA B45 Series-02 with B45S1- 
04 Supplement 


21 


Prefabricated Spa Shells: 


ANSIZ124.7-97. 


22 


Plastic Bathtub Liners: 


ANSIZ124.8-90. 


23 


Bathtubs and Whirlpool Bathtubs with Pressure Sealed Doors: 


ASMEA112.19.15-2001. 


24 


Emergency Showers and Eyewash Stations: 


ISEAZ358.1-2004. 


25 


Six Liter Water Closets Equipped with a Dual Flushing Device: 


ASME Al 12.19.14-2001 with 
Supplement 1-2003 


26 


Electro-hydraulic Water Closets: 


ASMEA112.19.13-2002 


^^ 


Enameled and Epoxy Coated Cast Iron and PVC Plastic Sanitary Floor Sinks: 


ASMEA112.6.7-2001 


N; : ;i-V;fil|£*> : ;:^l:|;!! 


1 


Anti-siphon Fill Valves (Ballcocks) for Gravity Water Closet Flush Tanks: 


ASSE 1002-1999, CSA Bl 25.3-05 


2 


Individual Thermostatic, Pressure Balancing, and Combination Pressure 
Balancing and Thermostatic Control Valves for Individual Fixture Fittings 


ASSE 1016-2005, ASME 
A112.18.1-2005/CSA B125.1-05 


3 


Divertors for Plumbing Faucets with Hose Spray, Anti-Siphon Type, 
Residential Application: 


ASSE 1025-1978; CSA B125-01. 


4 


PlumbingFixture Fittings: 


ASMEA112.I8.1-2005/CSA 
B125.1-05 


5 


Flushometers (Pressurized Flushing Devices): 


ASSE 1037-1990, CSA B125.3-05 


6 


Laboratory Faucet Vacuum Breakers : 


ASSE 1035-2002. 


7 


Showers, Hand Held: 


ASME Al 12.18.1-2005/ 
CSA B125.1-05 


8 


Supports for Off-The-Floor Plumbing Fixtures: 


ASME Al 12.6.1M-1997(R2002). 


9 


Trim for Water Closet Bowls, Tanks, and Urinals (dimensional standards): 


ASMEA112.19.5-1999, 
CSA B125.3-05 


10 


Flexible Water Connectors: 


ASME Al 12.18.6-2003. 


11 


Water Closet Seats, Plastic: 


ANSIZ124.5-1997. 


12 


Whirlpool Suction Fittings: 


ASME Al 12.19.8-1987 (R1996). 


13 


Performance Requirements for Backflow Protection Devices and Systems in 
Plumbing Fixture Fittings: 


ASMEA112.18.1-2005/CSA 
B125.1-05 


14 


Temperature Actuated Flow Reduction (TAFR) Valves for Individual Fixture 
Fittings: 


ASSE 1062-1997. 


15 


Individual Pressure Balancing In- Line Valves for Individual Fixture Fittings: 


ASSE 1066-1997. 


16 


Deck Mounted Bath/Shower Transfer Valves with Integral Backflow Protection: 


ASME Al 12.18.7-1999 (R2004) 


17 


Plumbing Fixture Waste Fittings: 


ASMEA112.18.2-2005/CSA 
B125.2-05 


18 


Thermoplastic Accessible and Replaceable Plastic Tube and Tubular 
Fittings; for Waste Connections (1-1/4", 1-1/2"): 


ASTM F409-02. 


19 


Dual Flush Devices for Water Closets: 


ASME Al 12.19.10 -2003 


20 


Plastic Fittings for Connecting Water Closets to the Sanitary Drainage 
System: 


ASME Al 12.4.3-1999 (R2004) 



2006 National Standard Plumbing Code-Illustrated 



97 



2.1 


Wall Mounted and Pedestal Mounted, Adjustable and Pivoting Lavatory 
and Sink Carrier Systems: 


ASME A112.3.4 - 2000 (R2004) 


22 


Water Closet Personal Hygiene Devices: 


ASME All 2.4.2 -2003 


23 


Safety Vacuum Release Systems (SVRS) for Spa and Hot Tub Suction Systems: 


ASME A112.4.2- 2002 


W^s (M Uy£WSi>WiiiM: yw> : ::- : ip|iwIing: appliances: : : ; : : :"t;Y [ : M ^M 


i 


Clothes Washers: 


AHAMHLW-1-2002,ASSE 1007- 
1986 


2 


Dishwashing Machines, Commercial : 


UL 921 Edition 5- 1996, 
ASSE 1004-1990 


3 


Dishwashers, Household: 


UL 749 Edition 7-1997, AHAM 

DW-1-2004, ASSE 1006-1986 


4 


Food Waste Grinder Units, Commercial: 


ASSE 1009-1990. 


5 


Food Waste Disposal Units, Household: 


AHAM FWD -1-2005, ASSE 
1008-1986, UL 430 Edition 6-2004 


6 


Hot Water Dispensers: 


ASSE 1023-1979. 


7 


Water heater, Gas, Volume I, Storage Type, 75,000 BTUH Input or less 


ANSI Z21.10.1-2004/CSA 4.1-04 


8 


Water Heaters, Gas, Volume III, Storage Type with Input above 75,000 BTUH 
Circulating and Instantaneous, Electric Storage Tank Type 


ANSI Z21.10.3-2004/CSA 4.3-04 


9 


Water Heaters, Household Electric Storage Tank Type: 


UL 174 Edition 11-2004 


10 


Water Heaters, Instantaneous. Electric, Point-of-use: 


UL 499 Edition 12-1997. 


11 


Water Heaters, Oil-Fired Storage Type: 


UL 732 Edition 5-1995. 


12 


Water Heater Relief Valve Drain Tubes: 


ASME A 1 1 2.4.1 -1 993 (R2002). 


13 


Water Softeners (CationExchange): 


NSF 44-2004 


14 


Reverse Osmosis Drinking Water Treatment Systems: 


NSF 58-2004 


15 


Macerating Toilet Systems and Related Components: 


ASM E Al 1 2.3.4 -2000 (R2004), 
CSA B45.9 of CSA B45 Series-02 
withB45Sl-04 Supplement 


VIII. VALVES AND APPURTENANCES 


1 


Backwater Valves: 


ASMEA112.14.1-2003,CSA 
B181.1-02 of CSA B1800 series 
(ABS), CSAB181.2-02 of CSA 
B1800 series (PVC) 


2 


Anti-siphon Fill Valves (Ballcocks) for Gravity Water Closet Flush Tanks: 


ASME 1002-1999; CSA Bl 25-01 


3 


Bronze Gate, Globe, Angle and Check Valves: 


MSS SP-80-2003. 


4 


Check Valves, Swing, Cast-iron: 


MSS SP-71-1997. 


5 


Cleanouts: 


ASMEA112.36.2M-1991(R2002). 


6 


Drain Valves, Water Heater: 


ASSE 1005-1999. 


7 


Flushometers (Pressurized Flushing Devices): 


ASSE 1037-1990; CSA B125-01. 


8 


Gate Valves, Cast-iron, 1 25# and 250#: 


MSS SP-70-1998. 


9 


Gate Valves, Iron Body (3" and larger): 


AWWAC500-02. 


10 


Water Pressure Reducing Valves: 


ASSE 1003-2001. 



98 



2006 National Standard Plumbing Code-Illustrated 



11 



12 



13 



14 



15 



16 



17 



19 



20 



21 



22 



23 



10 



11 



12 



13 



14 



15 



16 



17 



19 



20 



21 



Relief Valves and Automatic Gas Shut-off Devices for Hot Water Supply 



Temperature Actuated Mixing Valves for Hot Water Distributions Systems: 



Trap Seal Primer Valves, Potable Water Suppi i ed : 



Water Hammer Arrestors : 



Pre-Pressurized Potable Water Tanks (for thermal expansion): 



ANSI Z21.22-1999/CSA4.4-M99, 
ANSI Z21 .22A-2000/CSA 4.4A- 
2000, ANSI Z21.22B-2001/CSA 
4.4B-2001. 



ASSE 1017-2003; CSA B125.3-05 



ASSE 1018-2002. 



ASSE 1010-2004, PDI WH 201- 
1992. 



Reserved 



Ball Valves, Threaded, Socket- Welding, Solder Joints, Grooved, And Flared 
Ends: 



Water Temperature Limiting Devices 



Wall Hydrants, Vacuum Breaker Type, Freeze Resistant, Automatic Draining: 



Trap Seal Primer Devices - Drainage and Electronic Types: 



Wall Hydrants, Dual Check Baekflow Type, Freeze Resistant: 



Pressure Balancing In-Line Mixing Valves for Individual Fixture Fittings: 



Automatic Temperature Control Mixing Valves: 



IAPMO PS 88-2002. 



MSSSP-11 0(1996). 



ASSE 1070-2004. 



ASSE 1019-2004. 



ASSE 1044-2002. 



ASSE 1053-2004. 



ASSE 1066-1997. 



ASSE 1069-2005. 



IX. BACKFLOW PREVENTION DEVICES 



Air Gap Drain for Domesti c Dishwashers : 



Baekflow Preventers with Intermediate Atmospheric Vent: 



Detector Assembly, Double Check Type: 



Detector Assembly, Reduced Pressure Type: 



Double Check Valve Assembly: 



Dual Check Valve Type Baekflow Preventer: 



Dual Check Valve for Carbonated Beverage Dispensers: 



Reduced Pressure Principle Baekflow Preventer: 



Vacuum Breaker, Atmospheric (Pipe-Applied): 



Vacuum Breaker, Hose Connection: 



Vacuum Breaker, Laboratory Faucet: 



Vacuum Breaker, Pressure: 



ASSE 1021-2001. 



ASSE 1012-2002. 



ASSE 1048-2005. 



ASSE 1047-2005. 



ASSE 1015-2005. 



ASSE 1024-2004. 



ASSE 1032-2004. 



ASSE 1013-2005. 



ASSE 1001-2002. 



ASSE 1 01 1-2004. 



ASSE 1035-2002. 



Reserved 



Hose Connection Baekflow Preventers: 



Vacuum Breakers, Spill-Resistant: 



Air Gaps in Plumbing Systems: 



Performance Requirements for Baekflow Protection Devices and Systems in 
Plumbing Fixture Fittings : 



Air Gap Fittings for Use with Plumbing Fixtures, Appliances and 
Appurtenances: 



Outdoor Enclosures for Baekflow Prevention Assemblies: 



Baekflow Prevention Devices for Hand-Held Showers: 



Baekflow Preventers for (Carbonated) Beverage Dispensing Equipment: 



ASSE 1020-2004. 



ASSE 1052-2004. 



ASSE 1056-2002. 



ASMEA1 12.1. 2-2004. 



ASMEA112.18.3-2002; 
CSAB125-01. 



ASME All 2.1. 3-2000. 



ASSE 1060-1996. 



ASSE 1014-2005 



ASSE 1022-2003 



2006 National Standard Plumbing Code-Illustrated 



99 



10 



11 



12 



13 



15 



10 



11 



12 



13 



14 



15 



MJS< ELS WEOUS 



Copper Flashing (sheet): 



Lead Flashing (sheet): 



Pipe Hangers and Supports (materials, design, manufacture): 



Poly (Vinyl Chloride) (PVC) Plastic Flexible Concealed Water-Contaminant 
Membrane: 



ShowerPanLiner(PVCPlastic Sheeting): 



Chlorinated Polyethylene (CPE) Sheeting for Concealed Water-Containment 
Membrane: 



Shower Pan Liner (Plastic Sheeting): 



Grease Interceptors: 



Floor Affixed Supports for Off-the-Floor Plumbing Fixtures for Public Use : 



Framing Affixed Supports for Off-the-Floor Plumbing Fixtures: 



Plastics Piping System Components and Related Materials: 



Drinking Water System Components-Health Effects: 



Grease Recovery Devices (GRD): 



ASTMB370-03. 



ASTMB749-03. 



MSS SP-58-2002. 



ASTMD4551-96(R2001). 



ASTM D4551-96(R2001). 



ASTMD4068-01. 



ASTMD4068-01. 



ASMEA1 12.14.3-2000. 



ASME A112.6.1M-1997 (R2002). 



ASME Al 12.6.2-2001 (R2004). 



NSF 14-2004 with Addendum 1.0 



NSF 61-2004 with Addendum 1 .0 



14 Non Sewered Waste Disposal Systems Minimum Requirements 



Chemical Dispensing Systems 



ASMEA112.14.4-2001. 



ANSI Z4.3 -1987 (Rl 995). 



ASSE 1055-1997. 



XI. RECOMMENDED PRACTICES AND STANDARDS FOR QUALIFICATIONS, 



Installation of Ductile-Iron Water Mains and Appurtenances: 



Installing VitrifiedClay Pipe Lines: 



Safe Handling of Solvent Cements, Primers and Cleaners Used for Joining 
Thermoplastic Pipe and Fittings: 



Practice for Making Solvent-Cemented Joints with Poly( Vinyl Chloride) (PVC) 
Pipe and Fitting: . 



Underground Installation of Thermoplastic Pressure Pipe (up to 6"): 



Underground Installation of Thermoplastic Pipe for Sewers and Other Gravity 
Flow Applications: 



Recommended Practice for Installation of Thermoplastic Pipe and Corrugated 
Tubing in Septic Tank Leach Fields: 



Plast ic Fitting Patterns; Drain, Waste, and Vent (DWV): 
Selection and Application of Pipe Hangers and Supports: 



Fabrication and Installation Standards for Pipe Hangers and Supports: 



Field Test Procedures for Backflow Prevention Devices: 



Professional Qualification Standard for Backflow Prevention Assembly 
Testers, Repairers, and Surveyors: 



AWWAC600-99. 



ASTMC12-04el. 



ASTMF402-05. 



ASTM D2855-96 (R2002). 



ASTMD2774-04. 



ASTMD2321-04el. 



ASTMF481-97(R2002). 



ASTMD3311-02el. 



MSS SP-69-2003. 



MSS SP-89-2003. 



ASSE 5010-2004. 



ASSE Series 5000-2004 



Practice for Heat-Joining Poly olefin Pipe and Fittings: 



Practice for Electrofusion Joining Polylefin Pipe and Fittings: 



Making Capillary Joints by Soldering of Copper and Copper Alloy Tube and 
Fittings: 



ASTMD2657-03. 



ASTM F1290-98 (R2004). 



ASTMB828-02. 



100 



2006 National Standard Plumbing Code-Illustrated 



16 


Standard for Health Care Facilities: 


NFPA 99-2005. 


17 


Gas and Vacuum Systems: 


NFPA99C-2005. 


18 


Professional Qualification Standards for Medical Gas Systems Installers, 
Inspectors, Verifiers, Maintenance Personnel, and Instructors: 


ASSE Series 6000-2004. 


19 


Installation Procedures for Stainless Steel Drainage Systems: 


ASMEA1 12.3.1-1993 



NOTES FOR TABLE 3.1.3 

(1) See application sections of Chapter 3 for limitations on specific piping materials. 

(2) Pipe sizes contained in parentheses ( ) are provided for general information on the scope of the referenced standard and are 
not intended to limit use. 

(3) Alloy shall be marked on pipe and fittings. 



2006 National Standard Plumbing Code-Illustrated 



101 



Table 3.4 - MATERIALS FOR 


HOT WATER DISTRIBUTION 




POTABLE WATER 


COLD WATER DISTRIBUTION 






(1) 


(2) (3) (6) (7) 


WATER SERVICE PIPING 




1 


ABS Plastic Pipe, SDR (ASTM D2282) 


A 




\ 


2 


ABS Plastic Pipe, Schedule 40 or 80 (ASTM D1527) 


A 


X 


X 


3 


Brass Pipe (ASTMB43) 


A 


A 


A 


4 


Copper Pipe (ASTMB42) 


A 


A 


A 


5 


Copper Water Tube, Type K or L (ASTM B88) 


A 


A 


A 


6 


Copper Water Tube, Type M (ASTMB88) 


A 


A 


A 


7 


CPVC Plastic Pipe, Schedule 40, 80 (ASTM F441) 


A 


A 


A 


8 


CPVC Plastic Pipe, SDR (ASTM F442) 


A 


A 


A 


9 


CPVC Plastic Water Distribution Systems (ASTM D2846) 


A 


A 


A 


10 


Ductile Iron Pipe, Cement-lined (ASTMA377, ANSI/AWWAC151/A21.51) 


A 
A 


X 

III 


X 
__ 


11 


Fiberglass Pressure Pipe (AWWA C950) 


12 


Galvanized Steel Pipe (ASTM A53) 


A 
A 

A 
A 
A 


A 


A 

i 


13 


High-Density Polyethylene (HDPE) Plastic Pipe, SDR-1 1 (ASTM F714) 


14 


Reserved 


ftf 

H 


\ 


15 


PE Plastic Pipe, Schedule 40, 80 (ASTM D2447, rated 160 psi minimum at 73 deg F) 


16 


PE Plastic Pipe, SDR (ASTM D3035) 


17 


PE Plastic Pipe, SIDR (ASTM D2239, rated 160 psi minimum at 73 deg F) 


si- 

if 
■ 

A 


X 

"xT 

X 
A 


18 


PE Plastic Tube (ASTM D2737) 


A 
A 

A 


19 


PE Plastic Pressure Pipe and Tubing (AWWA C901, rated 160 psi minimum at 73 deg F) 


20 


PE-AL-PE Composite Pressure Pipe (ASTM F1282, CSA B 137.9 pipe with ASTM F1974 
metal insert fittings) 


21 


PEX-AL-PEX Composite Pressure Pipe (ASTM F1281, CSA B137.10pipe with ASTM 
F1974 metal insert fittings) 


A 


A 


A 


22 


Pressure-Rated Composite Pipe and Fittings for Elevated Temperature Service: (ASTM 
F1335) 


X 


A 


A 


23 


Crosslinked Polyethylene (PEX) Tubing (ASTM F876) 


A 


A 


A 


24 


ASTM F877 PEX Plastic Water Distribution Systems (ASTM F876 tubing with ASTM 
F1960 cold expansion fittings or ASTM Fl 807 metal insert fittings with ASTM F2098 
clamps) 


A 


A 


A 


25 


Crosslinked Polyethylene/Aluminum/Polyethylene (PEX-AL-PEX) Tubing, OD 
Controlled, SDR 9 (ASTM F2262) 


A 


A 


A 


26 


PVC Plastic Pressure Pipe, (AWWA C900) 


A 


\ 




27 


PVC Plastic Pipe, Schedule 40,80,120 (ASTM D1785) 


A 


28 


PVC Plastic Pipe, SDR (ASTM D2241) 


A 


lit 


X 


Approved 


A 


A 


A 

X 


Not Approved 


X X 



NOTES FOR TABLE 3.4 

(l)Piping for potable water shall be water pressure rated for not less than 160 psi at 73°F. 

(2)Piping for hot and cold water distribution shall be water pressure rated for not less than 100 psi at 1 80°F and 160 psi at 73°F. 

(3)Plastic piping materials shall comply with NSF 14. 

(4) Minimum SDR-1 1 for trenchless water service replacement systems. 

(5) Permitted for trenchless replacement of underground portions of piping within buildings. 

(6) See Table 3.4.2 for plastic water service piping. 

(7) See Table 3.4.3 for plastic hot and cold water distribution piping. 



102 



2006 National Standard Plumbing Code-Illustrated 



Table 3.4.2 
PLASTIC WATER SERVICE PIPE (2) 

(water pressure rated not less than 1 60 psi at 73 deg F) 



MATERIAL 


COMPOSITION 


DIMENSIONS 


JOINTS 


PIPE SIZE 


ABS(ASTMD1527) 


ABS 1208 


Schedule 40 


not threaded 


up thru 1 " 






Schedule 80 


threaded 


none 






Schedule 80 


not threaded 


up thru 2" 




ABS 1210 


Schedule 40 


not threaded 


up thru 1-1/2" 






Schedule 80 


threaded 


up thru 1 " 






Schedule 80 


not threaded 


up thru 4" 




ABS 1316 


Schedule 40 


not threaded 


up thru 5" 






Schedule 80 


threaded 


up thru 2-1/2" 






Schedule 80 


not threaded 


up thru 12" 




ABS 21 12 


Schedule 40 


not threaded 


up thru 3" 






Schedule 80 


threaded 


up thru 1-1/4" 






Schedule 80 


not threaded 


up thru 6" 


ABS (ASTM D2282) 


ABS 1316 


SDR 21 and lower 
(1) 


not threaded 


all sizes 




ABS 21 12 


SDR 1 7 and lower 
(1) 


not threaded 


all sizes 




ABS 1210 


SDR 13.5 


not threaded 


all sizes 




ABS 1208 


none 


none 


none 


PVC(ASTMD1785) 


PVC1120 


Schedule 40 


not threaded 


up thru 8" 






Schedule 80 


threaded 


up thru 4" 






Schedule 80 


not threaded 


up thru 24" 






Schedule 120 


threaded 


up thru 12" 






Schedule 120 


not threaded 


up thru 12" 




PVC 1220 


Schedule 40 


not threaded 


up thru 8" 






Schedule 80 


threaded 


up thru 4" 






Schedule 80 


not threaded 


up thru 24" 






Schedule 120 


threaded 


up thru 12" 






Schedule 120 


not threaded 


up thru 12" 




PVC2120 


Schedule 40 


not threaded 


up thru 8" 






Schedule 80 


threaded 


up thru 4" 






Schedule 80 


not threaded 


up thru 24" 






Schedule 120 


threaded 


up thru 1 2" 






Schedule 120 


not threaded 


up thru 1 2" 




PVC 21 16 


Schedule 40 


not threaded 


up thru 5" 






Schedule 80 


threaded 


up thru 2" 






Schedule 80 


not threaded 


up thru 24" 






Schedule 120 


threaded 


up thru 5" 






Schedule 120 


not threaded 


up thru 12" 




PVC 2112 


Schedule 40 


not threaded 


up thru 3" 






Schedule 80 


threaded 


up thru 1-1/4" 






Schedule 80 


not threaded 


up thru 6" 






Schedule 120 


threaded 


up thru 1-1/2" 






Schedule 120 


not threaded 


up thru 1 2" 



2006 National Standard Plumbing Code-Illustrated 



103 



Table 3.4.2 (Continued) 





PVC2110 


Schedule 40 


not threaded 


up thru 1-1/2" 






Schedule 80 


threaded 


up thru 1 " 






Schedule 80 


not threaded 


up thru 4" 






Schedule 120 


threaded 


up thru 1 " 






Schedule 120 


not threaded 


up thru 12" 


PVC(ASTMD2241) 


PVC 1 120 


SDR 26 or lower (1) 


not threaded 


all sizes 




PVC 1220 


SDR 26 or lower (1) 


not threaded 


all sizes 




PVC 2120 


SDR 26 or lower (1) 


not threaded 


all sizes 




PVC 21 16 


SDR 21 or lower (1) 


not threaded 


all sizes 




PVC 21 12 


SDR 17 or lower (1) 


not threaded 


all sizes 




PVC 21 10 


SDR 13.5 or lower 

(1) 


not threaded 


all sizes 


PVC (AWWA C900) 


12454- A, -B 


DR14 


not threaded 


up thru 12" 


CPVC (ASTM D2846) 


CPVC 4120 


SDR 11 


not threaded 


all sizes 


CPVC(ASTMF441) 


CPVC 4120 


Schedule 40 


not threaded 


up thru 12" 




CPVC 4120 


Schedule 80 


threaded 


up thru 4" 




CPVC 4120 


Schedule 80 


not threaded 


up thru 16" 


CPVC (ASTM F442) 


CPVC 4120 


SDR 26 or lower (1) 


not threaded 


up thru 12" 


PE (ASTM D2239) 


PE 3408 


SIDR9orlower(l) 


not threaded 


all sizes 




PE 3306 


SIDR7orlower(l) 


not threaded 


all sizes 




PE 3406 


SIDR7orlower(l) 


not threaded 


all sizes 




PE 2306 


SIDR7orlower(l) 


not threaded 


all sizes 




PE 2406 


SIDR7orlower(l) 


not threaded 


all sizes 




PE 2305 


SIDR 5.3 


not threaded 


all sizes 




PE 1404 


none 


none 


none 


PE (ASTM D2447) 


PE 2306 


Schedule 40 


not threaded 


1/2" 






Schedule 80 


not threaded 


up thru 1-1/4" 




PE 2406 


Schedule 40 


not threaded 


1/2" 






Schedule 80 


not threaded 


up thru 1-1/4" 




PE 3306 


Schedule 40 


not threaded 


1/2" 






Schedule 80 


not threaded 


up thru 1-1/4" 




PE 3406 


Schedule 40 


not threaded 


1/2" 






Schedule 80 


not threaded 


up thru 1-1/4" 




PE 2305 


Schedule 40 


not threaded 


none 






Schedule 80 


not threaded 


up thru 3/4" 




PE 1404 


Schedule 40 


not threaded 


none 






Schedule 80 


not threaded 


1/2" 


PE (ASTM D2737) 


PE2305 


SDR 7.3 


not threaded 


all sizes 




PE 2306 


SDR 9 


not threaded 


all sizes 




PE 2406 


SDR 9 


not threaded 


all sizes 




PE 3306 


SDR 9 


not threaded 


all sizes 




PE 3406 


SDR 9 


not threaded 


all sizes 




PE 3408 


SDR 11 


not threaded 


all sizes 



104 



2006 National Standard Plumbing Code-Illustrated 



Table 3.4.2 (Continued) 



PE(ASTMD3035) 


PE 3408 


SDR 11 or lower (1) 


not threaded 


all sizes 




PE 2406 


SDR 7 


not threaded 


all sizes 




PR 1404 


none 


none 


none 


PE(ASTMF714) 


PE 


SDR 11 


not threaded 


all sizes 


PE(AWWAC901) 


PE 2406 


IDR7 


not threaded 


up thru 3" (pressure class 
160) 




PE 3406 


IDR7 


not threaded 


up thru 3" (pressure class 
160) 




PE 3408 


IDR9 


not threaded 


up thru 3" (pressure class 
160) 




PE 2406 


DR9 


not threaded 


up thru 3" (pressure class 
160) 




PE 3406 


DR9 


not threaded 


up thru 3" (pressure class 
160) 




PE 3408 


DR11 


not threaded 


up thru 3" (pressure class 
160) 


PE-AL-PE(ASTMF1282) 


PE-AL-PE 


ASTM F 1282 


not threaded 


all sizes 


PEX (ASTM F876) 


PEX 1006 


SDR 9 


not threaded 


all sizes 


PEX (ASTM F877) 


PEX 


SDR 9 


not threaded 


all sizes 


PEX-AL-PEX (ASTM 
F1281) 


PEX-AL-PEX 


ASTMF1281 


not threaded 


all sizes 


PEX-AL-PEX (ASTM 
F2262) 


PEX-AL-PEX 


SDR 9 


not threaded 


all sizes 


Composite (ASTM Fl 335) 


PE-AL-PE 


ASTM Fl 335 


compression 


all sizes 


Composite (ASTM F 1 335) 


PEX-AL-PE 


ASTMF1335 


compression 


all sizes 



NOTES 

( 1 ) Lower SDR numbers have heavier wall thicknesses and higher pressure ratings. 

(2) Refer also to the manufacturer's recommendations, instructions and limitations. 

Table 3.4.3 
PLASTIC HOT AND COLD WATER DISTRIBUTION PIPING (1) 

(water pressure rated for not less than 1 00 psi at 180 deg F and 160 psi at 73 deg F) 



MATERIAL 


COMPOSITION 


DIMENSIONS 


JOINTS 


PIPE SIZES 


CPVC (ASTM D2846) 


CPVC 4120 


SDR 11 


not threaded 


all sizes 


CPVC(ASTMF441) 


CPVC 4 120 


Schedule 40 


not threaded 


up thru 2" 






Schedule 80 


threaded 


up thru 2 






Schedule 80 


not threaded 


up thru 2" 


CPVC (ASTM F442) 


CPVC 4120 


SDR 11 &1 3.5 


not threaded 


all sizes 


PEX (ASTM F876) 


PEX 1006 


SDR 9 


not threaded 


all sizes 


PEX (ASTM F877) 


PEX 


SDR 9 


not threaded 


all sizes 


PE-AL-PE (ASTM F 1282) 


PE-AL-PE 


ASTM F 1282 


not threaded 


all size 


PEX-AL-PEX (ASTM F2262) 


PEX-AL-PEX 


SDR 9 


not threaded 


all sizes 


PEX-AL-PEX (ASTM F1281) 


PEX-AL-PEX 


ASTM F 1281 


not threaded 


all sizes 


Composite Pipe (ASTM F 1335) 


PE-AL-PE 


ASTM D 1335 


compression 


all sizes 


Composite Pipe (ASTM F1335) 


PEX-AL-PE 


ASTMD1335 


compression 


all sizes 



NOTES 

( 1 ) Refer also to the manufacturer's recommendations, instructions and limitations. 



2006 National Standard Plumbing Code-Illustrated 



105 



Table 3.5 - MATERIALS FOR 


ABOVEGROUND WITHIN BUILDINGS 




SANITARY WASTE & DRAIN 

(1) (2) (3) 


UNDERGROUND WITHIN BUILDINGS 






SEWERS OUTSIDE OF BUILDINGS 




1 


ABS Pipe and Fittings, Schedule 40 DWV (ASTM D2661) 


A 


A 


A 


2 


ABS Pipe - Cellular Core (ASTM F628) and DWV Fittings 


A 


A 


A 


3 


ABS Sewer Pipe and Fittings (for sewers outside of buildings) (ASTM D2751) (1) 


A 


111 


X 

X 
A 


4 


ABS and PVC Composite Sewer Pipe (ASTM D2680) 


A 


X 

X 


5 


Brass Pipe (ASTM B43) 


X 


6 


Cast-iron Soil Pipe and Fittings - Bell and Spigot (ASTM A74) 


A 


A 


A 


7 


Cast-iron Soil Pipe and Fittings - Hubless (CISPI 301, ASTM A888) 


A 


A 


A 


8 


Cellular Core PVC Sewer and Drain Pipe (ASTM F891) 


A 


A 


X 

"x 

A 
X 


9 


Cellular Core PVC Sewer and Drain Pipe (ASTM F891) (4) 


* 4 


10 


Cellular Core PVC DWV Pipe, IPS Schedule 40 (ASTM F89 1 ) 


A 
A 


A 
X 


11 


Concrete Drain Pipe. Nonreinforced (ASTM CI 4) 


12 


Concrete Drain Pipe, Reinforced (ASTM C76) 




■. 


A 


13 


Copper Pipe (ASTMB42) 


A A 


A 


14 


Copper Tube - DWV (ASTM B306) and Copper Drainage Fittings (ASME B16.23) 


A 


A 


A 


15 


Copper Water Tube - K,L,M (ASTM B88) and Copper Drainage Fittings (ASME B16.23) 


A 


A 


A 
X 


16 


Fiberglass Sewer and Pressure Pipe (ASTM D3754) and Fiberglass Non-Pressure Pipe Fittings 
(ASTM D3840) 


A 


X 


17 


Galvanized Steel Pipe (ASTM A53) and Cast-iron Drainage Fittings (ASME B16.12) 


X 


|it§ 


A 


18 


High-Density Polyethylene (HDPE) Plastic Pipe (ASTM F714) (6) 


A X J X 


19 


PVC Pipe and Fittings, DWV (ASTM D2665) 


A 


A 


A 


20 


PVC Schedule 40 Drainage and DWV Fabricated Fittings (ASTM F1866) 


A 


A 


A 


21 


PVC Sewer Pipe (PS-46) and Fittings (ASTM F789) (2) 


A 


X 


X 


22 


PVC Sewer Pipe (PSM) and Fittings (ASTM D3034) (2) 




X 


X 

A 


23 


Stainless Steel DWV Systems - Type 316L (ASME Al 12.3.1) (5) 


A 1 A 


24 


Stainless Steel DWV Systems - Type 304 (ASME Al 12.3.1) (5) 


1 x 


. X 




25 


Vitrified Clay Pipe - Standard Strength (ASTM C700) 


A 


■ X 


X 


26 


Vitrified Clay Pipe - Extra Strength (ASTM C700) 


A 


A 
A 

fell 


A 


Approved 


A 

X 


Not Approved 


X 



NOTESFORTABLE3.5 

( 1 ) Plastic drain, waste, and vent piping classified by standard dimensionn ratio shall be SDR 26 or heavier (lower SDR number). 

(2) Plastic sewer pipe classified by pipe stiffness shall be PS-46 or stiffer (higher PS number). 

(3) Piping shall be applied within the limits of its listed standard and the manufacturer's recommendations. 

(4) PS- 1 00 pipe or stiffer (higher PS number) . 

(5) Alloy shall be marked on pipe and fittings 

(6) Minimum SDR- 1 7 for trenchless sewer replacement systems. 



106 



2006 National Standard Plumbing Code-Illustrated 



Table 3.6 - MATERIALS 




ABOVEGROUND 




FOR VENT PIPING (1) 


UNDERGROUND 




1 


ABS Pipe and Fittings, Schedule 40 DWV (ASTM D2661) 


A 


A 


2 


ABS Pipe - Cellular Core (ASTM F628) and DWV Fittings 


A 


A 


3 


Brass Pipe (ASTM B43) 


\ 


A 


4 


Cast-iron Soil Pipe and Fittings -Bell and Spigot (ASTM A74) 


A 


A 


5 


Cast-iron Soil Pipe and Fittings -Hubless (CISPI 301, ASTM A888) 


A 


A 


6 


Cellular Core PVC DWV Pipe, IPS Schedule 40 (ASTM F891) 


A 


A 


7 


Copper Pipe (ASTMB42) 


X 


A 


8 


Copper Tube - DWV (ASTM B306) and Copper Drainage Fittings (ASME B 1 6.23) 


A 


A 


9 


Copper Tube - K, L, M (ASTM B88) and Copper Drainage Fittings (ASME B 16.23) 


A 


A 


10 


Galvanized Steel Pipe (ASTM A53) and Cast-iron Drainage Fittings (ASME B16.12) 


x -. 


A 


11 


PVC Pipe and Fittings, DWV (ASTM D2665) 


A 


A 


12 


PVC Schedule 40 Drainage and DWV Fabricated Fittings (ASTM F1866) 


A 


A 


13 


Stainless Steel DWV Systems-Type 316L (ASME Al 12.3.1) (2) 


A 


A 


14 


Stainless Steel DWV Systems-Type 304 (ASME Al 12.3.1) (2) 


\ 


A 


15 


3.25" OD PVC Pipe and Fittings, DWV (ASTM D2949) 


A 

A 


A 


16 


Vitrified Clay Pipe - Extra Strength (ASTM C700) 


X j 








Approved 
Not Approved 


A 

A 




A 

"xl 



NOTES FOR TABLE 3.6 

(1) Piping shall be applied within the limits of its listed standards and the manufacturer's 
recommendations. 

(2) Alloy shall be marked on pipe and fittings. 



2006 National Standard Plumbing Code-Illustrated 



107 



Table 3.7 - MATERIALS 


ABOVEGROUND WITHIN BUILDINGS 




FOR STORM DRAINAGE 

(1) 


UNDERGROUND WITHIN BUILDING 






SEWERS OUTSIDE OF BUILDING 


1 


ABS Pipe and Fittings, Schedule 40 DWV (ASTM D2661) 


A 


A 


A 


2 


ABS Pipe - Cellular Core (ASTM F628) and DWV Fittings 


A 


A 


A 


3 


ABS Sewer Pipe and Fittings (ASTM D275 1) (2) (3) 


A 
A 
\ 


X 1 X 


4 


ABS and PVC Composite Sewer Pipe (ASTM D2680) 


six 


5 


Brass Pipe (ASTMB43) 


X 




6 


Cast-iron Soil Pipe and Fittings - Bell and Spigot (ASTM A74) 


A 

A 


A 


A 


7 


Cast-iron Soil Pipe and Fittings - Hubless (CISPI 301, ASTM A888) 


A A 


8 


Cellular Core PVC Sewer and Drain Pipe (ASTM F891) (3) 


A 


X I X : 


9 


Cellular Core PVC Sewer and Drain Pipe (ASTM F891) (4) 


1111 


A 


\ | 
A 

xl 


10 


Cellular Core PVC DWV Pipe, IPS Schedule 40 (ASTM F891) 


A 


A 

X 


11 


Concrete Drain Pipe, Nonreinforced (ASTM CI 4) 


A 


12 


Concrete Drain Pipe, Reinforced (ASTM C76) 


A 
A 


X 


\ | 


13 


Copper Pipe (ASTMB42) 


X 
A 


A 
A 


14 


Copper Tube - DWV (ASTM B3 06) and Copper Drainage Fittings (ASMEB 16.23) 


15 


Copper Tube - K,L,M (ASTM B88) and Copper Drainage Fittings (ASMEB 16.23) 


A 


A 


A 


16 


Galvanized Steel Pipe (ASTM A53) and Cast-Iron Drainage Fittings (ASME B16.12) 




r X 


A 

X 


17 


PE- High-Density Polyethylene (HDPE) Plastic Pipe, SDR- 17, (ASTM F714)(6) 


A 


X 


18 


PVC Pipe and Fittings, DWV (ASTM D2665) 


A 


A 


A 


19 


PVC Schedule 40 Drainage and DWV Fabricated Fitting (ASTM F1866) 


A 


A 


A 


20 


PVC Sewer Pipe (PS-46) and Fittings (ASTM F789) 


A 


\ 


X 


21 


PVC Sewer Pipe (PSM) and Fittings (ASTM D3034) (2) (3) 


A 


X 
A 


\ 
A 
A 
X 
\ 
A 
X 


22 


Stainless Steel DWV Systems-Type 316L (ASME A112.3.1)(5) 


A 


23 


Stainless Steel DWV Systems-Type 304 (ASME Al 12.3. 1)(5) 


X:,. 


24 


Vitrified Clay Pipe - Standard Strength (ASTM C700) 


A 


\ 


25 


Vitrified Clay Pipe - Extra Strength (ASTM C700) 


A 


A 






Approved 
Not Approved 


A 


A 
X 



NOTESFORTABLE3.7 

(1) Piping shall be applied within the limits of its listed standards and the manufacturer's recommendations. 

(2) SDR 3 5 pipe or heavier (lower SDR number) . 

(3) PS-46 pipe or stiffer (higher PS number). 

(4) PS- 1 00 pipe or stiffer (higher PS Number). 

(5) Alloy shall be marked on pipe and fittings 

(6) Minimum SDR- 1 7 for trenchless sewer systems. 



108 



2006 National Standard Plumbing Code-Illustrated 



Table 3.8 - MATERIALS FOR FOUNDATION DRAINS AND SUB-SOIL DR AINAHF 


1 


1 


Clay Drain lile (AS I'M C49K) 


A 

A 


2 
3 


Concrete Drain Tile (ASTM C412) 


Perforated Concrete Pipe (ASTM C444) 


A 


4 


Corrugated Polyethylene Tube (ASTM F405) 


A 


5 


SR Plastic Drain Pipe and Fittings, Perforated (ASTM D2852) 


A 


6 


PVC Sewer Pipe and Fittings, Perforated (ASTM D2729) 


A 


7 


Stainless Steel DWV Systems -Type 3 16L (ASME A112.3 1) 


A 


8 


Vitrified Clay Pipe, Perforated, Standard and Extra Strength f ASTM C70(T> 


A 









Approved 


A 



2006 National Standard Plumbing Code-Illustrated t a« 



Blank Page 



110 2006 National Standard Plumbing Code-Illustrated 







Joints and Connections 



4.1 GENERAL REQUIREMENTS 

4.1.1 Tightness 

Joints and connections in the plumbing system shall be gas tight and watertight for the pressure required by 
test, with the exceptions of those portions of perforated or open joint piping that are installed for the purpose 
of collecting and conveying ground or seepage water to the underground storm drains. 



Comment: Perforated and open-joint piping is also used for the piping in absorption trenches for private 
sewage disposal systems. See Section 16.9.5. 



4.1.2 JointStandards 

a. Pipe and tube shall be cut 90° or perpendicular to the pipe center lines. 

b. The inside diameter of pipe and tube ends shall be reamed, filed, or smoothed to size of bore and all 
chips removed. All burrs on the outside of the pipe and butt ends shall be removed before the installation. 

c. Pipe and tube shall engage into fittings the full manufacturer's design depth of the fitting socket. 

d. Male pipe threads shall be made of sufficient length to ensure the proper engagement. 

e. Pipe shall not extend into a fitting or other pipe to such a depth that it will impede or restrict the design 
flow. 

f. Joints made by bonding, welding, brazing, solvent cementing, soldering, burning, fusion or mechanical 
means shall be free from grease or other substances not specifically required to achieve a satisfactory joint. 

g. Pipe sealing or lubricating compound required for threaded pipe joints shall be applied to the male pipe 
end only and shall be insoluable and nontoxic. 



Comment: For industry standards for the various joining methods, refer to Table 3.1.3 - Part IV Pipe 
Joints, Joining Materials, Couplings, Gaskets. 



4.1.3 Expansion Joints 

Mechanical type expansion joints requiring or permitting adjustment shall be accessible for adjustment and/or 
replacement. 

4.1.4 Increasers and Reducers 

Where different sizes of pipes or pipes and fittings are to be connected, increaser and reducer fittings or 
bushings shall be used. (See Section 2.4.3) 



2006 National Standard Plumbing Code-Illustrated 111 



4.2 TYPES OF JOINTS FOR PIPING MATERIALS 

4.2.1 Caulked 

4.2.1.1 Cast-Iron Soil Pipe 

Lead caulked joints for cast-iron hub and spigot soil pipe shall be firmly packed with oakum or hemp and filled 
with molten lead not less than 1 inch deep and not to extend more than 1/8 inch below the rim of the hub. 
No paint, varnish, or other coatings shall be permitted on the jointing material until after the joint has been 
tested and approved. Lead shall be run in one pouring and shall be caulked tight. See Figure 4.2.1.1 



OAKUM 




LEAD - ONE CONTINUOUS POUR 
SET WITH CAULKING IRONS 



CAST IRON 
HUB END 




CAST IRON 
SPIGOT END 



Figure 4.2.1.1 
A LEAD CAULKED JOINT IN CAST IRON SOIL PIPE 



4.2.1.2 Cast-iron Water Pipe 

Lead caulked j oints for cast-iron ball and spigot water pipe shall be firmly packed with clean dry jute, or treated 
paper rope packing. The remaining space in the hub shall be filled with molten lead according to the following 



schedule: 



Pipe Size 
Up to 20 inches 
24, 30, 36 inches 
Larger than 36 inches 



Depth of Lead 
2-1/4 inches 
2-1/2 inches 
3 inches 



Lead shall be run in one pouring and shall be caulked tight. See Figure 4.2.1.2 



APPROVED SEALING MATERIAL 

<M 




LEAD - ONE CONTINUOUS POUR 
SET WITH CAULKING IRONS 



CAST IRON 

WATER PIPE 

HUB END 




CAST IRON 
WATER PIPE 
SPIGOT END 



Figure 4.2.1.2 
A LEAD CAULKED JOINT IN IRON WATER PIPE 



112 



2006 National Standard Plumbing Code-Illustrated 



4.2.2 Threaded 

The threads in taper threaded pipe joints shall conform to ASME B. 1 .20. 1 . See Figure 4.2.2 



TAPERED PIPE THREADS (ASME B1.20.1) 



REAMED CHAMFER 




Figure 4.2.2 
A THREADED PIPE JOINT 

4.2.3 Wiped 

Joints in lead pipe or fittings, or between lead pipe or fittings and brass or copper pipe, ferrules, solder nipples, 
or traps, shall be full wiped joints. Wiped joints shall have an exposed surface on each side of a joint not less 
than 3/4 inch and at least as thick as the material being jointed. Wall or floor flange lead-wiped joints shall be 
made by using a lead ring or flange placed behind the joints at wall or floor. Joints between lead pipe and 
cast-iron, steel, or wrought iron shall be made by means of a caulking ferrule, soldering nipple, or bushing. 
See Figure 4.2.3 



WIPED LEAD SOLDER 
LEAD PIPE 



COPPER PIPE 




Figure 4.2.3 
A WIPED JOINT ON LEAD PIPE 

4.2.4 Soldered 

a. Soldered joints in copper water piping shall be made using wrought pressure fittings complying with ASME 
B 1 6.22, cast pressure fittings complying with ASME B 1 6. 1 8, or cast copper alloy flanges complying with ASME 
B 16.24. 

NOTE: Short-cup brazing fittings complying with ASME B 1 6.50 and bearing the mark "BZ" shall not be used 
where joints are soldered. 

b. Soldered joints in copper drain and vent piping shall be made with wrought drainage fittings complying with 
ASME B 16.29 or cast drainage fittings complying with ASME B 16.23. 

c. Soldered joints shall be made in accordance with ASTM B828. 

d. Solder shall comply with ASTM B32. Flux shall comply with ASTM B8 13. 

e. Solder for joints in potable water piping shall contain not more than 0.2% lead. See Figure 4.2.4 



2006 National Standard Plumbing Code-Illustrated 



113 



Comment: The limit on lead in solder filler metal is to reduce the level of lead in drinking water in 
accordance with the EPA Safe Drinking Water Act. 



COUPLING 



- SOLDER FILLER METAL 



J 



COPPER TUBE 



£ ■^'^'^"^XTO^V v*v V, v. N \ '.\ WIS 



COPPER TUBE 



Figure 4.2.4 
A SOLDERED JOINT 

4.2.5 Flared 

Flared joints for copper water tube shall be made with fittings complying with ASME B 16.26. The tube shall 
be reamed and then expanded with an approved flaring tool. See Figure 4.2.5 



FLARE NUT 



WRENCH FLAT 



ANNEALED COPPER TUBING 




NOTES: 

1 . A long flare nut is shown. Short flare nuts are permissible where vibration is not a factor. 

Figure 4.2.5 
A FLARED COPPER JOINT 

4.2.6 Mechanically Crimped (Pressed) Joints 

a. Copper fittings for water supply and distribution, designed for mechanically crimped (pressed) connections to 
ASTM B88 hard drawn copper water tube, shall include an O-ring gasket complying with NSF 61 for potable water. 
EXCEPTION: Mechanically crimped (pressed) joints shall be permitted with annealed copper water tube when such 
use is included in the fitting manufacturer's technical data and installation instructions. 

b. The fittings shall comply with the material and sizing requirements of ASME B 1 6.22 (wrought copper or copper 
alloy fittings) or ASME B 1 6. 1 8 (cast copper alloy fittings). 

c. During installation, the tube end shall be deburred and depth-marked to permit visual verification of full insertion 
of the tube into the fitting socket. 

d. The joint shall be crimped (pressed) using a tool approved by the manufacturer of the fitting. 

e. The joints shall be rated by the manufacturer for not less than 200 psig at 1 80 deg F. 

f. The fittings shall be permitted to be installed in concealed locations. 



114 



2006 National Standard Plumbing Code-Illustrated 



4.2.7 Push-on Joints 

a. Copper fittings for water supply and distribution, designed for manual push-on connections to ASTM B88 
hard drawn copper tubing, shall include corrosion-resistant gripping fingers and an O-ring gasket complying 
with NSF 61 for potable water. 

EXCEPTION: Push-on fittings shall be permitted to be used with annealed copper water tube and OD sized 
CPVC and PEX tubing if such use is included in the fitting manufacturer's technical data and installation 
instructions. 

b. The fittings shall comply with the material and sizing requirements of ASME B 16.22 (wrought copper or 
copper alloy fittings) or ASME B 1 6. 1 8 (cast copper alloy fittings). 

c. During installation, the tube end shall be deburred and depth-marked to permit visual verification of full 
insertion of the tube into the fitting socket. 

d. The fittings shall be rated by their manufacturer for not less than 200 psig at 1 80 deg F. 

e. The fittings shall be permitted to be installed in concealed locations. 

4.2.8 Brazed 

4.2.8.1 General 

a. Brazed joints in copper tubing shall be made in accordance with accepted industry practice. See Appendix 
L for an accepted practice for general plumbing. 

b. Brazed joints in medical gas and vacuum piping shall be made in accordance with NFPA 99 or NFPA 99C. 

4.2.8.2 Fittings 

a. Fittings in copper tubing with brazed joints shall be wrought solder joint fittings complying with ASME 
B 1 6.22 or short-cup brazing fittings complying with ASME B 1 6.50. Short-cup brazed joint fittings shall be 
clearly marked by the manufacturer to differentiate them from solder-joint fittings and avoid their being used 
in piping with soldered joints. 

b. Fittings for medical gas and vacuum piping shall be as required by NFPA 99 or NFPA 99C. 

4.2.8.3 Mechanically Formed Tee Branches 

a. Mechanically formed tee branches shall be permitted in copper tubing in water distribution systems. The 
branch connections shall be formed with appropriate tools and joined by brazing. The branch tube end shall 
be notched and dimpled with two sets of double dimples. The first dimples shall act as depth stops to prevent 
the branch tube from being inserted beyond the depth of the branch collar. The second dimples shall be 
1/4" above the first dimples and provide a visual means of verifying that the branch connection has been 
properly fitted. The dimples in the branch tube shall be in line with the run of the main. The joints shall be 
brazed in accordance with Section 4.2.8.1 and ASTM F2014. 

b. Mechanically former tee branches shall not be permitted in drainage piping. 

4.2.9 Cement Mortar 

a. Where permitted as outlined in Sec. 2.4.4, cement mortar joints shall be made in the following manner: 1 . 
A layer of jute or hemp shall be inserted into the annular joint space and packed tightly to prevent mortar from 
entering the interior of the pipe or fitting. 

2. Not more than 25 percent of the annular space shall be used for jute or hemp. 

3. The remaining space shall be filled in one continuous operation with a thoroughly mixed mortar composed 

of one part cement and two parts sand, with only sufficient water to make the mixture workable by hand. 

4. Additional mortar of the same composition shall then be applied to form a one to one slope with the barrel 
of the pipe. 



2006 National Standard Plumbing Code-Illustrated -t t r 



5. The bell or hub of the pipe shall be left exposed for inspection. 

6. When necessary, the interior of the pipe shall be swabbed to remove any mortar or other material that 
may have found its way into such pipe. 



Comment: Cement mortar joints have been virtually eliminated by the use of alternate joining methods 
and materials. 



4.2.10 Burned Lead (Welded) 

Burned (welded) joints shall be made in such a manner that the two or more sections to be joined shall be 
uniformly fused together into one continuous piece. The thickness of the weld shall be at least as thick as the 
leadbeingjoined. 



Comment: The added welding material must be of the same composition as the lead pipe being joined. 



4.2.11 Mechanical (Flexible or Slip Joint) 
4.2.11.1 Stainless Steel DWV Systems 

a. Joints in stainless steel DWV systems shall be made with an elastomeric o-ring of a material that is suitable 
for the intended service. 

b. Joints between stainless steel drainage systems and other piping materials shallbe made with an approved 
adapter coupling. 

4.2.11.2 Cast-iron Soil Pipe 

a. Hubless pipe: Joints for hubless cast-iron soil pipe and fittings shall be made with an approved elastomeric 
sealing sleeve and corrosion resisting clamping device or shall be made using a rigid unshielded TPE coupling 
with center stop installed per Section 4.3.8d. 

b. Hub and Spigot: Joints for hub and spigot cast-iron soil pipe and fittings, designed for use with a compressed 
gasket, may be made using a compatible compression gasket that is compressed when the spigot is inserted 
into the hub of the pipe. 

See Figures 4.2.11.2-A and -B 



ELASTOMERIC 
GASKET 




VZZZZZZZZZZZZZZZZL 



HUBLESS 
CAST IRON 



SHIELD 

CORROSION RESISTANT CLAMP AND SCREWS 



mzzzzzzzzzzzzzz 




HUBLESS 
CAST IRON 



SHIELDED COUPLING 



Figure 4.2.11.2-A 
A SHIELDED COUPLING ON HUBLESS CAST IRON SOIL PIPE 



116 



2006 National Standard Plumbing Code-Illustrated 



COMPRESSION GASKET 

rzzzzzzzzzzzzzzzzzzzsz rz / urfrfr^f^fT7 r? 



/j ft i > i / / / / , ,. / 




Figure 4.2.11.2-B 
A CAST IRON HUBBED JOINT WITH A COMPRESSION GASKET 



4.2.11.3 Cast-iron Water Pipe 

Mechanical joints in cast-iron water pipe shall be made with a flanged collar, a rubber ring gasket, and the 
approved number of securing bolts. See Figure 4.2.11.3 




TEE HEAD BOLT 



GLAND 

WNWWWWWl 




Figure 4.2.11.3 
A MECHANICAL JOINT ON IRON WATER PIPE 



2006 National Standard Plumbing Code-Illustrated 



117 



4.2.11.4 Clay Pipe 

Joints in piping and/or fittings shall be made using flexible compression joints. See Figure 4.2.11.4 



RUBBER COUPLING 




CORROSION RESISTANT 
CLAMPS AND SCREWS 



. . ^ ^| T^^^ ^~r!r r ~~^ t 



CLAY PIPE- 
PLAIN END 



CLAY PIPE- 
PLAIN END 



Figure 4.2.11.4 
AN UNSHIELDED COUPLING ON PLAIN END CLAY PIPE 



4.2.11.5 Concrete pipe 

Flexible joints between lengths of concrete pipe may be made using approved compression type joints or 
elastomeric materials born on the spigot end and in the bell (or hub) end of the pipe. See Figure 4.2.11.5 







O-RING 



CONCRETE PIPE 
BELL END 



CONCRETE PIPE 
SPIGOT END 



\. 




Figure 4.2.11.5 
A JOINT IN BELL AND SPIGOT CONCRETE PIPE 

4.2.11.6 Elastomeric Sleeves 

Mechanical joints on drainage pipes below ground shall be made with an elastomeric seal conforming to ASTM 
D3212, CSA B602 or ASTM CI 173. Joints shall be installed in accordance with the manufacturer's 
instructions. 



118 



2006 National Standard Plumbing Code-Illustrated 



4.2.12 Reserved 



4.2.13 Reserved 



4.2.14 Plastic 

Joints in plastic piping shall be made with approved fittings by either solvent cement or heat joined connections; 
approved couplings consisting of elastomeric sleeves and corrosion resisting metal screw clamps; approved 
insert fittings; approved mechanical fittings; or threaded joints according to approve standards. PVC solvent 
cemented joints shall use an approved primer appropriate for the material used. An approved purple colored 
primer and solvent cement not purple in color shall be used in j oining PVC pipe and fittings. An approved color 
primer not orange in color and solvent cement orange in color or a single step solvent cement that is yellow 
in color and is third party certified as conforming to ASTM F493 shall be used in joining 1/2 inch through 2 
inch in diameter CPVC pipe and fittings that are manufactured in accordance with ASTM D2846. 
EXCEPTION: Primer shall be used for CPVC pipe and fittings where recommended by the manufacturer(s) 
of the pipe and fittings. See Figures 4.2.14-A through-F 



PRIMER (IF REQUIRED) AND SOLVENT 
CEMENT APPLIED TO PIPE ENDS 
AND FITTING SOCKET 




WIPED BEAD 



Figure 4.2.14-A 
A SOLVENT CEMENT JOINT IN PLASTIC DWV OR WATER PIPING 



ELASTOMERIC GASKET JOINT FOR UNDERGROUND 
BUILDING DRAINS OR SEWERS 




Figure 4.2.14-B 
AN ELASTOMERIC GASKET JOINT FOR UNDERGROUND PLASTIC DWV PIPING 



2006 National Standard Plumbing Code-Illustrated 



119 



ELASTOMERIC 
GASKET 



PLASTIC DWV PIPE 




SHIELD 

CORROSION RESISTANT CLAMPING SCREWS 

PLASTIC DWV PIPE 



CORROSION RESISTANT CLAMPS 



Figure 4.2.14-C 
A SHIELDED COUPLING ON PLASTIC DWV PIPING 



PLASTIC PIPE WITH SOCKET (BELL) END 







f € 



\JW>' H> U J> 




PRIMER (IF REQUIRED) AND SOLVENT CEMENT 
ON PIPE END AND INSIDE OF SOCKET 



WIPED BEAD 




Figure 4.2.14-D 

A SOLVENT CEMENT JOINT IN SOCKET (BELL) END PLASTIC PRESSURE PIPE 




CORROSION RESISTING CLAMP DEVICE 
OR CRIMP RING ASSEMBLY 



PLASTIC TUBING 



^ — INSERT FITTING 
NOTES 

1. Some manufacturers recommend two clamps on each side of the fitting for additional joint strength. 



Figure 4.2.14-E 
AN INSERT FITTING JOINT IN PLASTIC TUBING 



120 



2006 National Standard Plumbing Code-Illustrated 



I 



HEAT FUSED AREAS 




Figure 4.2.1 4-F 
A HEAT FUSED JOINT IN PLASTIC WATER PIPING 

4.2.15 Slip 

Slip joints shall be made using approved packing or gasket material, or approved ground joint brass compres- 
sion rings. Ground joint brass connections that allow adjustment of tubing but provide a rigid joint when made 
up, shall not be considered as slip joints. See Figure 4.2.1 5-A and-B ~ 



WASHER 



COMPRESSION SLIP NUT 




METAL OR PLASTIC TUBING 



NOTES: 

1 . Straight tubular joints having washers are slip joints and require access. Refer to the definition of 
accessible 

Figure 4.2.15-A 
A SLIP JOINT IN DRAIN TUBING 



2006 National Standard Plumbing Code-Illustrated 



121 



BRASS COMPRESSION RING 
OR FERRULE 



LOCKNUT 




METAL OR PLASTIC TUBING 



NOTES: 

1 . When a compression joint does not permit free movement when assembled, it is not considered to 
be a slip joint and does not need to be accessible. Refer to the definition of "accessible". 



Figure 4.2.15-B 
A COMPRESSION JOINT IN DRAIN TUBING 



4.2.16 Expansion 

Expansion joints shall be of approved type and its material shall conform with the type of piping in which it is 
installed. See Figures 4.2.16-A,-B, and-C 



Comment: Expansion joints must to be accessible for adjustment or replacement Refer to the definition 
of "accessible". 



SOLVENT CEMENT 



O-RINGS 



SOLVENT CEMENT 




Figure 4.2.16-A 
AN EXPANSION JOINT FOR PLASTIC DWV PIPING 



122 



2006 National Standard Plumbing Code-Illustrated 




Figure 4.2.16-B 
A MECHANICAL EXPANSION JOINT IN PRESSURE PIPING 




INLET 

- — ADJUSTABLE EXPANSION SLEEVE 
WRENCH GRIP 

WING NUT AND BOLT 
(3 AT 120° APART) 
PACKING GLAND 



PACKING 



BODY 



OUTLET 



Figure 4.2.16-C 
AN EXPANSION JOINT FOR ROOF DRAINS 



4.2.17 Split Couplings 

a. Split couplings consisting of two or more parts and a compression gasket, designed for use with grooved 
or plain end pipe and fittings, shall be permitted to be used for water service piping, hot and cold domestic 
water piping, storm water conductors and leaders, and sump pump discharge piping. The complete joint 
assembly shall be suitable for the intended use and comply with a standard listed in Table 3. 1 .3. 
b. Galvanized steel pipe or other interior coated pipe shall not be joined using rolled grooves. 
See Figure 4.2.17 



2006 National Standard Plumbing Code-Illustrated 



123 



HOUSING 
GROOVED PIPE 



GASKET 

GROOVED PIPE 




Figure 4.2.17 
A GROOVED PIPE JOINT 



4.2.18 Butt Fusion 

ASTM F714 high-density polyethylene (HDPE) pipe and ASTM D3261 fittings shall be joined by butt fusion 
in accordance with ASTM D2657. 

4.2.19 Bending 

Changes in direction in copper water tube shall be permitted to be made by the use of factory or field bends. Field 
bends shall be made in accordance with Table 4.2.19. Bends shall be made only with bending equipment and 
procedures intended for that purpose. Hard drawn tubing shall not be bent with tubing benders intended for only 
annealed (soft) tube. All bends shall be smooth and free from buckling, cracks, and other evidence of mechanical 
damage. 



Table 4.2.19: BEND] 


[NG COPPER TUBE 


Nominal Tube Size -in. 


Tube Type 


Temper 


Min. Bend Radius, in. 


1/4 inch 


K,L 


Annealed (soft) 


3/4" 


3/8 inch 


K,L 


Annealed (soft) 


1-1/2" 


3/8 inch 


K,L,M 


Drawn (hard) 


1-3/4" 


1/2 inch 


K,L 


Annealed (soft) 


2-1/4" 


1/2 inch 


K,L,M 


Drawn (hard) 


2-1/2" 


3/4 inch 


K,L 


Annealed (soft) 


3" 


3/4 inch 


K,L 


Drawn (hard) 


3" 


1 inch 


K,L 


Annealed (soft) 


4" 


1-1/4 inches 


K,L 


Annealed (soft) 


9" 



4.3 TYPES OF JOINTS BETWEEN DIFFERENT PIPING MATERIALS 

4.3.1 Vitrified Clay to Other Material 

Joints between vitrified clay and other piping materials shall be made with an approved joint. See Figures 
4.3.1-A and-B 



124 



2006 National Standard Plumbing Code-Illustrated 



COMPRESSION 
JOINT SEALER 




NOTES: 

1 . The rubber rings must be sized to adapt to the different outside diameters (O.D.) of the different 
piping materials being joined. 

2. There are hundreds of different adapters available forjoining different materials, different pipe sizes, 
and different wall thickness, as well as clay pipe from different manufacturers. 

Figure 4.3. 1-A 
A RUBBER RING TRANSITION JOINT TO VITRIFIED CLAY PIPE 



SHIELD 



ELASTOMERIC 
GASKET 



77777//////////////, 




CORROSION RESISTANT CLAMPING SCREWS 



CORROSION RESISTANT CLAMPS 



NOTES: 

1 . Externally clamped couplings (shielded and unshielded) are a common way of making transition 
connections from vitrified clay pipe to other piping materials. Various sized gaskets are available to 
adapt to the different outside diameters (O.D.) of the piping materials being joined. 



Figure 4.3.1.B 

AN EXTERNALLY CLAMPED TRANSITION COUPLING JOINT 

TO VITRIFIED CLAY PIPE 



4.3.2 Reserved 

4.3.3 Reserved 



2006 National Standard Plumbing Code-Illustrated 



125 



4.3.4 Threaded Pipe to Cast-Iron 

Joints between steel or brass and cast-iron pipe shall be either caulked or threaded or shall be made with 
approved adapter fittings. See Figure 4.3.4 



THREADED STEEL OR BRASS PIPE 



I ' " "'^_ . ; 



OAKUM 



LEAD 



CAST IRON PIPE 



r S I . 

^ K\\\\\^\\W \\\\Wsnv^| 



Figure 4.3.4 
A THREADED PIPE TO CAST IRON ADAPTER FITTING 



4.3.5 Lead to Cast-iron or Steel 

Joints between lead and cast-iron or steel pipe shall be made by means of wiped joints to a caulking ferrule, 
soldering nipple, bushing, or by means of a mechanical adapter. See Figure 4.3.5 




LEAD PIPE 



WIPED LEAD 



BRASS CAULKING FERRULE 



Figure 4.3.5 
A WIPED LEAD TRANSITION JOINT 



126 



2006 National Standard Plumbing Code-Illustrated 



4.3.6 Cast-Iron to Copper Tube 

Joints between cast-iron and copper tube shall be made by using an approved brass or copper caulking ferrule 
and by properly soldering the copper tube to the ferrule. See Figure 4.3.6 



OAKUM 



LEAD 

SOLDERED 




CAULKING FERRULE 



Figure 4.3.6 
A CAULKING FERRULE FOR CAST IRON TO SWEAT COPPER TRANSITION 



4.3.7 Copper Tube to Threaded Pipe Joints 

a. Joints from copper tube to threaded pipe shall be made as follows: 

1. DWV Systems: with copper or brass threaded adapters. 

2. Potable Water Systems and Galvanized Steel Pipe: cast brass threaded adapters, dielectric unions or 
flanges (1-1/2" and larger), or dielectric waterway fittings that comply with IAPMO PS 66. 

3. To any Non-Ferrous Piping: copper or brass threaded adapter. 

b. The adapter fitting shall be soldered to the tubing by approved methods, and the threaded section as- 
sembled with National Pipe Threads— Tapered (NPT). 

See Figures 4.3.7 - A and - B 



COPPER TUBE 



BRASS MALE ADAPTER 




THREADED FITTING 



Figure 4.3.7-A 
A SWEAT COPPER TO THREADED PIPE TRANSITION 



2006 National Standard Plumbing Code-Illustrated 



127 



COPPER SOLDER JOINT 
CONNECTOR 



STEEL NUT 




DIELECTRIC 
(INSULATOR ) 



INSULATING 
GASKET 



STEEL BODY 



TAPERED PIPE THREADS 



COPPER SOLDER JOINT ■ 
CONNECTOR 



MACHINE 
BOLTS 



DIELECTRIC 
(INSULATOR 





INSERT NSF/FDA 
LISTED LINING 
(INSULATOR) 



GROOVED, THREADED 

OR PLAIN END 



WATERWAY FITTING 



ZINC ELECTROPLATED 
STEEL CASING 



FULLY SEPARATED 
DISSIMILLAR METALS 



COPPER ADAPTER 



IRON 
FLANGES 



TAPERED PIPE THREADS - 



Figure 4.3.7-B 
DIELECTRIC UNION, FLANGE, AND WATERWAY FITTING 

4.3.8 Special Joints and Couplings for Drainage Piping 

a. Joints between two different drainage piping materials or between different size piping, of the same or 
different material, shall be made using fittings or mechanical couplings that are designed for the specific 
application, including adapter fittings, hubless pipe couplings, slip-on couplings, transition couplings, and repair 

couplings. 

b. Fittings and couplings for use under this Section shall either (1) comply with a standard listed in Table 
3 . 1 .3, (2) be listed or labeled by a recognized listing agency, or (3) be approved by the Authority Having 
Jurisdiction if such products are not listed or labeled. Installation shall comply with the coupling 
manufacturer's instructions and intended use. 

c. Shielded couplings shall consist of a flexible elastomeric sealing sleeve, a protecting and supporting 
continuous metal shield or shear ring, and metal screw clamping bands. All metal parts shall be corrosion- 
resisting. Shielded couplings shall be capable of withstanding a shear test based on a load of 50 pounds per 
inch of nominal pipe diameter, and shall be permitted to partially support the pipe being joined when such 
installation is recommended by the manufacturer's instructions. Shielded couplings may be installed 
aboveground or underground, as intended by the manufacturer. 

d. Mechanical unshielded couplings using thermoplastic elastomer gaskets shall consist of a rigid or semi- 
rigid sealing sleeve and corrosion-resisting metal screw clamping bands. Mechanical unshielded couplings 
using thermoplastic elastomer gaskets shall not be installed where the operating internal or external tempera- 



128 



2006 National Standard Plumbing Code-Illustrated 



hires exceed 130°F (54°C) or are below 0°F (-18°C). The pipe shall be supported on both sides of the 
coupling within 18 inches of the centerline of the coupling. Mechanical unshielded couplings using thermo- 
plastic elastomer gaskets shall be permitted aboveground or underground. Mechanical unshielded couplings 
using thermoplastic elastomer gaskets shall not be installed in construction that has a fire rating that restricts 
the use of flammable materials or be installed in through penetrations or plenums without additional fire 
resistance protection. 

e. Flexible unshielded couplings shall consist of an elastomeric sealing sleeve and corrosive-resisting metal 
screw clamping bands. The use of flexible unshielded couplings shall be limited to joints in underground sewer, 
drain or vent piping. 

f. Couplings installed aboveground shall include center stops. 
EXCEPTION: Slip-on repair couplings used for repair or rework. 

g. The shear tests required under this Section shall be performed in accordance with the shear test 
procedures specified under any of the coupling standards listed in Table 3.1 .3 that include such tests. 

See Figures 4.3.8-A through-D 



COUPLING SHIELD 



FLEXIBLE ELASTOMERIC 
SEALING SLEEVE 




CORROSION RESISTANT CLAMPING SCREWS 



CENTER STOP (WHERE REQUIRED) 



1 CORROSION RESISTANT CLAMPS 

NOTES: 

1 . Shielded couplings can be used aboveground and underground. They can partially support the pipe. 
Center stops are required except for repair couplings. 



Figure 4.3.8-A 
A SHIELDED COUPLING ON DRAINAGE PIPING 



RIGID OR SEMI-RIGID SEALING SLEEVE 

FLEXIBLE ELASTOMERIC 
SEALING SLEEVE 




CORROSION RESISTANT CLAMPING SCREWS 



CENTER STOP (WHERE REQUIRED) 



' CORROSION RESISTANT CLAMPS 
NOTES: 

1 . Rigid unshielded couplings can be used aboveground and underground. They cannot support the 
pipe. The pipe must be independently supported. Center stops are required except for repair 
couplings. 

Figure 4.3.8-B 
A RIGID UNSHIELDED COUPLING ON DRAINAGE PIPING 



2006 National Standard Plumbing Code-Illustrated 



129 



FLEXIBLE ELASTOMERIC ADAPTOR 
SEALING SLEEVE 



i CORROSION RESISTANT CLAMPING SCREWS 



^ZZZ^ZZH^ 



' I 
I 



SHIELDED COUPLING 



DIRECTION OF 
DRAINAGE FLOW 



CORROSION RESISTANT CLAMPS 



Figure 4.3.8-C 
A TRANSITION CONNECTION USING A SHIELDED COUPLING 



FLEXIBLE UNSHIELDED COUPLING 



CORROSION RESISTANT 
CLAMPING SCREWS 




DIRECTION OF 
DRAINAGE FLOW 



CORROSION RESISTANT CLAMPS 



NOTES: 

1 . Flexible unshielded couplings are limited to underground sewer, drain, and vent piping. Center 

stops are required except for repair couplings. The couplings cannot support the pipe. The piping 

must be properly backfilled to avoid stresses on the couplings. 

Figure 4.3.8-D 
A TRANSITION CONNECTION USING A FLEXIBLE UNSHIELDED COUPLING 

4.3.9 ABS or PVC Plastic DWV to Other Material 

a. Threaded Joints: ABS or PVC DWV joints when threaded shall use the proper male or female threaded 
adapter. Use only approved thread tape or lubricant seal or other approved material as recommended by the 
manufacturer. Threaded joints shall not be over-tightened. After hand tightening the joint, make a one-half to 
one full turn with a strap wrench. 

b. Cast-iron Hub Joints: Joints may be made by caulking with lead and oakum or by use of a compression 



130 



2006 National Standard Plumbing Code-Illustrated 



gasket that is compressed when the plastic pipe is inserted into the cast-iron hub end of the pipe. No adapters 
are required for this connection. 

c. Cast-iron Spigot Ends, Schedule 40 Steel Pipe or Copper DWV Tube: Joints between these materials and 
plastic shall be joined with an approved adapter fitting. 

d. The solvent cemented non-pressurejointbetweendissimilarplastic materials, ABS/PVCbuilding drains and/ 
or building sewers, shall be made using an ASTM D3 1 3 8 solvent cement intended for AB S/PVC transition joints . 

See Figures 4.3.9-A through-D 



THREAD LUBRICANT 



MALE ADAPTOR - NPT X SOCKET 



PRIMER (IF REQUIRED) AND SOLVENT CEMENT 
APPLIED TO PIPE END AND INSIDE OF SOCKET 



PLASTIC PIPE 




THREADED COUPLING 
OR FITTING 



Figure 4.3.9-A 
A PLASTIC DWV THREADED MALE ADAPTER 



OAKUM 



LEAD 




CAST IRON 

PIPE 




PLASTIC 
PIPE 



NOTES: 

1 . Plastic pipe that is lead caulked must be solid plastic. Molten lead will melt cellular core plastic 
pipe. 

Figure 4.3.9-B 
A LEAD CAULKED JOINT FOR PLASTIC DWV TO CAST IRON HUB 



2006 National Standard Plumbing Code-Illustrated 



131 



COMPRESSION GASKET 



=2^1==== 




PLASTIC 
PIPE 



Figure 4.3.9-C 
A COMPRESSION GASKETED JOINT FOR PLASTIC DWV TO CAST IRON HUB 



■ PLASTIC PIPE 

- WIPED BEAD 



PRIMER (IF REQUIRED) AND SOLVENT CEMENT 
APPLED TO PIPE END AND INSIDE OF SOCKET 



LEAD 



CAST IRON PIPE 




PLASTIC ADAPTER FITTING 



NOTES: 

1 . Plastic fittings that are lead caulked musty be solid plastic. Molten lead will melt cellular core pipe 
fittings. 

Figure 4.3.9-D 
A LEAD CAULKED PLASTIC SOCKET JOINT TO CAST IRON PIPE 



132 



2006 National Standard Plumbing Code-Illustrated 



4.4 CONNECTIONS BETWEEN DRAINAGE PIPING AND CERTAIN 
FIXTURES 

a. Connections between drainage piping and floor outlet plumbing fixtures shall be made by means of an 
approved flange that is attached to the drainage piping in accordance with the provisions of this chapter. The 
floor flange shall be set on and securely anchored to the building structure. 

b. Connections between drainage piping and wall hung water closets shall be made by means of an approved 
extension nipple or horn adapter. 

c. Connections shall be bolted to the flange or carrier using corrosion resisting bolts or screws, or assemblies 
recommended by the manufacturer. 

4.5 WATERPROOFING OF OPENINGS 

a. Joints around vent pipes at the roof shall be made watertight by the use of lead, copper, aluminum, plastic, or 
other approved flashing or flashing materials. See Section 12.4.7. 

b. Exterior wall openings shall be made watertight. 



2006 National Standard Plumbing Code-Illustrated 1 33 



Blank Page 



134 2006 National Standard Plumbing Code-Illustrated 







^ewgwwff 







Traps, Cleanouts and Backwater Valves 

5.1 SEPARATE TRAPS FOR EACH FIXTURE 

a. Plumbing fixtures shall be separately trapped by a water seal trap placed as close as possible to the fixture 
outlet. 

b. The vertical distance from the fixture outlet to the trap weir shall not exceed 24 inches. 

c. Fixtures shall not be double-trapped unless a relief vent is provided between the two traps. 

d. Fixture designs having integral dual traps within the fixture shall be permitted. 
EXCEPTIONS: 

(1) Fixtures that have integral traps. 

(2) A combination-plumbing fixture may be installed on one trap provided the waste outlets are not more than 
30 inches apart. 

(3) One trap may be installed for up to three (3) compartment sinks, laundry trays or lavatories that are 
immediately adjacent to each other in the same room, and where the trap is centrally located when three such 
fixtures are installed. 

(4) No clothes washer or laundry tub shall be discharged to a trap serving a kitchen sink. 

(5) As otherwise permitted by this Code. 
See Figures 5.1-A through-D 



LAVATORY 



FIXTURE 

OUTLET - 

FIXTURE 
TAILPIECE 



^ 



MAXIMUM DISTANCE FROM 
FIXTURE OUTLET TO TRAP WEIR 



24 
INCHES 




TRAP 
WEIR 



NOTES: 

1 . Vertical distances greater than 24" may induce self-siphoning of the trap seal due to the momentum 
of the drainage flow. 

Figure 5.1 - A 
THE VERTICAL DISTANCE FROM A FIXTURE OUTLET TO ITS TRAP WEIR 



2006 National Standard Pumbing Code-Illustrated 



135 



WATER CLOSET 




Figure 5.1 - B 
A FIXTURE WITH AN INTEGRAL TRAP 



SINK 



SINK 



END OUTLET — ^ 



LET -p 



£ 



30" 

MAXIMUM 

NOTES: 

1. Refer to the definitions of "Continuous Waste" and "Combination Fixture". 

Figure 5.1 - C 
A CONTINUOUS WASTE WITH END OUTLET 




CENTER OUTLET 



NOTES: 

1 . Refer to the definitions of "Continuous Waste" and "Combination Fixture". 

Figure 5.1 - D 
A CONTINUOUS WASTE WITH CENTER OUTLET 



136 



2006 National Standard Pumbing Code-Illustrated 



5.2 SIZE OF FIXTURE TRAPS 

Fixture trap size (nominal diameter) shall be sufficient to drain the fixture rapidly and in no case less than given in 
Table 5.2. No trap shall be larger than the drainage pipe into which it discharges. Integral traps shall conform to 
appropriate standards. 



Comment: A drainpipe that is smaller than the trap to which it is connected could create an obstruction 
to flow through the trap. 



5.3 GENERAL REQUIREMENTS FOR TRAPS 

5.3.1 Design of Traps 

Fixture traps shall be self-scouring and shall have no interior partitions except where such traps are integral 
with the fixture or where corrosion resistant materials of plastic or glass are used. Solid connections, slip 
joints, or couplings may be used on the trap inlet, trap outlet, or within the trap seal. (See Section 7.4.6 ) See 
Figures 5.3.1-A through-C. Refer to Sections 4.2.15 and 7.3.7 for slip joints and their required 
access. 



ro 




SOLID CONNECTIONS 



HAH3ZZ3 



- FIXTURE TRAP 

NOTES: 

1 . Access is not mandatory for traps with solid connections. 



Figure 5.3.1 - A 
A FIXTURE TRAP WITH SOLID CONNECTIONS 



ESCUTCHEON 



NOTES: 

1 . Slip joints must be accessible 




WALL 



Figure 5.3.1 - B 
A FIXTURE TRAP WITH SLIP JOINTS 



2006 National Standard Pumbing Code-Illustrated 



137 




GROUND JOINT 



SLIP JOINT 



NOTES: 

1 . Only the slip joint must be accessible. 

Figure 5.3.1 - C 
A FIXTURE TRAP WITH THREE DIFFERENT TYPES OF JOINTS 



5.3.2 Trap Seals 

Each fixture trap shall have a liquid seal of not less than two inches and not more than four inches 
EXCEPTIONS: 

(1) Interceptors in Chapter 6. 

(2) Special conditions such as accessible fixtures, a deeper seal may be required by the Authority Having 
Jurisdiction. 

See Figure 5.3.2 



INLET — 



- CROWN WEIR OF TRAP 
OUTLET 



DIP OF TRAP 




FLOW 



NOTES: 

1 . The minimum trap seal depth of 2" is based on the design criteria for the vent piping. Trap seals 
deeper than 4" will tend to trap solids and create a breeding ground for bacteria. 



Figure 5.3.2 
TRAP SEAL DEPTH 



5.3.3 Trap Setting and Protection 

Traps shall be set level with respect to their water seals and, where necessary, shall be protected from 
freezing. See Figure 5.3.3 



138 



2006 National Standard Pumbing Code-Illustrated 



KITCHEN SINK WITH 

FOOD WASTE DISPOSAL UNIT 



90" FLANGED TAILPIECE ON 
FOOD WASTE DISPOSAL 



NOTES 



1_ 



fa 




Tilted traps may self-siphon because of the reduction in the effective depth of the trap seal. 
Where freeze protection is necessary, thermal insulation alone will not prevent freezing, only delay 
it. Traps should be located in heated spaces. 

Where seasonal facilities are shutdown during the winter, fixture traps can be filled with an anti- 
freeze solution that will not damage the traps or drain piping. 



Figure 5.3.3 
TRAPS MUST BE LEVEL AND PROTECTED FROM FREEZING 



Table 5.2 
MINIMUM SIZE OF NON-INTEGRAL TRAPS 



Plumbing Fixture 



Bathtub (with or without overhead shower) 



Bidet 



Clothes washing machine standpipe 



Combination sink and wash (laundry) sink with food waste grinder unit 



Combination kitchen sink, domestic dishwasher, and food waste grinder 



Dental unit or cuspidor 



Dental lavatory 



Drinking fountain 



Dishwasher, commercial 



Dishwasher, domestic (non-integral trap) 



Floor drain 



Food waste grinder, commercial use 



Food waste grinder, domestic use 



Kitchen sink, domestic, with food waste grinder unit 



Kitchen sink, domestic 



Lavatory, common 



Lavatory (barber shop, beauty parlor or surgeon's) 



Lavatory, multiple type (wash fountain or wash sink) 



Laundry tray (1 or 2 compartments) 



Shower stall or shower drain (single shower head) 



Shower stall or shower drain (multiple shower heads) 



Sink (surgeon's) 



Sink (flushing rim type, flush valve supplied) 



Sink (service type with floor outlet trap standard) 



Sink (service type with P trap) 



Sink, commercial (pot, scullery, or similar type) 



Sink, commercial (with food grinder unit) 



Trap Size in 
inches 



l 



1 X A 



1V4(1) 



i v 2 



l % 



l % 



l % 



1 Vi 



1 1/2 



1 Vi 



1 V2 



IVi 



1 Vi 



1 V2 



1 V2 



1 !4 



1 V2 



(1) Separate trap required for wash tray and separate trap required for sink compartment with 
food waste grinder. 



2006 National Standard Pumbing Code-Illustrated 



139 



5.3.4 BuildingTraps 

Building traps shall not be installed except where required by the Authority Having Jurisdiction. Each building 
trap when installed shall be provided with a cleanout and with a relieving vent or fresh air intake on the inlet 
side of the trap that shall be at least one-half the diameter of the drain to which it connects. Such relieving 
vent or fresh air intake shall be carried above grade and terminate in a screened outlet located outside the 
building. 



Comment: Building traps are no longer installed in modern plumbing systems. They provide a collec- 
tion point for solids and other waste that may cause line stoppages. Building traps also prevent the 
building vent system from venting the building sewer. The Authority Having Jurisdiction may require 
building traps if the sewer gas in the municipal sewage system is particularly corrosive or aggressive and 
could damage the drain, waste, and vent piping in the building. 



5.3.5 Prohibited Traps 

a. The following types of traps shall be prohibited: 

1 . Traps that depend upon moving pails to maintain their seal. 

2. Bell traps. 

3. Crown vented traps. 

4. Separate fixture traps that depend on interior partitions for their seal, except if made from plastic, glass 
or other corrosion resistant materials. 

5. "S" traps, of uniform internal dimension. 

6. Drum traps. 

b. Hair interceptors, precious metal interceptors and similar appurtenances shall be permitted as required. 
See Figure 5.3.5 




-1 w 




\ (J ,,,,,.; 


J 


v.. 



y=y 



BELL TRAP 



BALL TRAP WITH 
MOVING PARTS 





TRAP IS CROWN VENTED 
IF DISTANCE (X) IS WITHIN 
TWO PIPE DIAMETERS (Y) 



PARTITION TRAP 
(Note 1) 



CROWN VENTED TRAP 




if 



DRUM TRAP 



■S- TRAP OF TUBULAR DESIGN 

NOTES: 

1 . Traps having internal partitions are permitted if constructed of plastic, glass, or other corrosion 
resistant material. 

Figure 5.3.5 
PROHIBITED TRAPS 



140 



2006 National Standard Pumbing Code-Illustrated 



5.3.6 Trap Seal Maintenance 

a. Traps that could lose their seal due to evaporation because of infrequent use shall be equipped with a 
readily accessible means to replenish the trap seal or a trap primer conforming to ASSE 1018 or ASSE 1044 

b. In addition to the priming requirement above, the installation of a sealing component on the fixture drain 
outlet to reduce trap seal loss shall be permitted. Sealing devices shall be properly sized for the drain outlet 
on which they are installed. They shall permit the fixture to drain completely and shall not leave standing 
water or waste on or around the device. 

5.4 DRAINAGE PIPE CLEANOUTS 

5.4.1 CleanoutSpacing 

a. Cleanouts in horizontal drainage lines shall be spaced at intervals not exceeding the following values: 

4" pipe size or less: 75 feet 
5" size and larger: 100 feet 

b. The distance referred to in Sections 5.4. la shall include the developed length of the cleanout pipe. 
See Figure 5.4.1 




"X" (See Notes) 



PIPE SIZE "D" 



NOTES 

1 . The maximum spacing "X" for pipes 4" and smaller is 75 feet, including the developed length to the 
cleanout opening. 

2. The maximum spacing "X" for pipes 5" and larger is 1 00 feet, including the developed length to the 
cleanout opening. 

3. Manholes may be used for cleanouts in building drains or building sewers (or branches thereof) that 
are 8" size or larger. The maximum spacing is 300 feet. Refer to Section 5.4.10. 

Figure 5.4.1 
CLEANOUT SPACING ON HORIZONTAL DRAIN LINES 



5.4.2 Building Sewer 

Cleanouts, when installed on an underground building sewer, shall be extended vertically to or above the 
finished grade level. See Figure 5.4.2 



2006 National Standard Pumbing Code-Illustrated 



141 




FINISHED GRADE 



BUILDING SEWER 



NOTES: 

1 . Cleanouts must have flush top covers if located in a walkway or other paved area. 

2. The length of the vertical extension to grade must be included in the developed length between 
cleanouts. 

Figure 5.4.2 
A SEWER CLEANOUT EXTENDED TO FINISHED GRADE 



5.4.3 Change of Direction 

a. Cleanouts shall be installed at changes of direction in drainage piping made with 60°, 70° and 90° fittings. 
EXCEPTION: Where there are multiple changes of direction, not more than one cleanout shall be required in 

40 feet of run. 

b. Cleanouts shall not be required where changes of direction are made with one or more 22 1/2° or 45° 
fittings. See Figure 5.4.3 



FLOW 




FLOW 

NOTES: 

1 . A cleanout is not required at Points "B", "C", & "D" if the distance from Point "A" to Point "D" is 

less than 40 feet. 

Figure 5.4.3 

WHERE CLEANOUTS ARE REQUIRED AT CHANGES IN DIRECTION 



5.4.4 Cleanouts for Concealed Piping 

Cleanouts for concealed piping shall be extended through and terminate flush with the finished wall or floor; 
or pits or chases may be left in the wall or floor, provided they are of sufficient size to permit removal of the 
cleanout plug and proper cleaning of the system. See Figure 5.4.4 



142 



2006 National Standard Puinbing Code-Illustrated 







WYE AND 
TEST PLUG 
ARRANGEMENT 



ACCESS PLATE 



I 



1 




CLEANOUT TEE 
OR TEST TEE 



RETAINING SCREW 
CLEANOUT COVER 



Figure 5.4.4 
ACCESS TO CONCEALED CLEANOUTS 



5.4.5 Base of Stacks 

a. A cleanout shall be provided near the base of each vertical waste or soil stack and located 6 inches 
above the flood level rim of the lowest fixture on the lowest floor. If there are no fixtures installed on the 
lowest floor, the cleanout shall be installed at the base of the stack. 

b. For buildings with a floor slab, a crawl space of less than 18 inches, or where a stack cleanout is not 
accessible, the cleanout shall be installed in the building drain or building sewer, not more than five feet 
outside the building wall. 

c. Rain leaders and conductors connected to a building storm sewer shall have a cleanout installed at the 
base of the outside leader or inside conductor before it connects to the horizontal drain. 

See Figures 5.4.5-A,-B, and-C 



/— SANITARY DRAIN OR STORMWATER STACK 

on. 



CLEANOUT 




Figure 5.4.5 - A 
A CLEANOUT NEAR THE BASE OF A STACK 



2006 National Standard Pumbing Code-Illustrated 



143 



INACCESSIBLE 
SOIL OR WASTE 
STACK 



I — FOUNDATION WALL 



BUILDING DRAIN 




CLEANOUT 



NOTES: 

1 . The extension of a cleanout for access in not considered to be a dead end. 

Figure 5.4.5 - B 
A CLEANOUT EXTENDED TO OUTSIDE OF THE BUILDING FOR ACCESS 



-Vi 



P 



RAIN LEADER 



V^ 



- ALTERNATE CLEANOUT TEE 



( 






VS 



rj TO BUILDING 
STORM SEWER 



NOTES: 

1 . Cleanouts are required near the base of exterior rain leaders and interior conductors when they 
connect to a building storm drain or building storm sewer. 

Figure 5.4.5 - C 
A CLEANOUT NEAR THE BASE OF A RAIN LEADER 

5.4.6 Building Drain and Building Sewer Junctions and the Property Line 

a. There shall be a cleanout near the junction of a building drain and building sewer either inside or outside 
the building wall. 

b. A cleanout shall be placed in the building sanitary sewer and building storm sewer at the property line 
and brought to the surface per the requirements of the Authority Having Jurisdiction. and brought to the 
surface per the requirements of the Authority Having Jurisdiction. 

See Figures 5.4.6 - A and - B 



144 



2006 National Standard Pumbing Code-Illustrated 



BUILDING /, 
WALL — — VA 




BUILDING 
DRAIN 



Figure 5.4.6 - A 
A CLEANOUT AT THE JUNCTION OF THE BUILDING DRAIN AND BUILDING SEWER 




NOTES: 

1 . The cleanout and cleanout connection to the sewer required by Section 5.4. 6. b must be within the 
property. 

Figure 5.4.6 - B 
A CLEANOUT AT THE PROPERTY LINE 



5.4.7 Direction of Flow 

Cleanouts shall be installed so that the cleanout opens in the direction of the flow of the drainage line or at 
right angles thereto. See Figure 5.4.7 



2006 National Standard Pumbing Code-Illustrated 



145 




TWIN 
CLEANOUT 



TWO-WAY 
CLEANOUT 



COMBINATION 

WYE & 1/8TH BEND 



NOTES: 

1 . Cleanouts must have flush top covers if located in a walkway or other paved area. 



Figure 5.4.7 
THE FLOW DIRECTION OF CLEANOUTS 



5.4.8 Connections to Cleanouts Prohibited 

a. Cleanout plug openings in other than drainage pattern fittings shall not be used for the installation of new 
fixtures or floor drains. 

b. If a cleanout fitting or cleanout plug opening is removed from a drainage pattern fitting in order to extend 
the drain, another cleanout of equal access and capacity shall be provided in the same location. 

5.4.9 Cleanout Size 

Cleanout size shall conform with Table 5.4.9. 



Table 5.4.9 
SIZE OF CLEANOUTS 



Nominal 
Piping Size (inches) 



Nominal 
Size of Cleanout (inches) 



l'/4 
172 

2 

3 

4&6 

8&10 

12&15 



l'A 

172 

2 
3 
4 
6 

8 



(1 ) See Section 5.4. 10 for sizes 12" or larger for building sewers. 

(2) See Section 5.4.13 for cleanout equivalents. 



146 



2006 National Standard Pumbing Code-Illustrated 



5.4.10 Manholes for Large Pipes 

a. Manholes shall be provided as cleanouts for building sewers 12" size and larger. Manholes shall be 
provided at every change of size, alignment, direction, grade, or elevation. The distance between manholes 
shall not exceed 300 feet. 

b. Manholes may be provided in lieu of cleanouts in underground building sewers, building drains, and 
branches thereof, 8" size and larger. 

c. Such manholes shall comply with the requirements of Section 5.4.10a. 

d. If manholes are installed indoors, they shall have a bolted, gas-tight cover. 

e. Manhole construction shall comply with the standards of the Authority Having Jurisdiction. 
See Figure 5.4.10 



CHANGE OF 
DIRECTION 




CHANGE OF 
ELEVATION 



300' 
MAXIMUM 



Figure 5.4.10 
LOCATION AND SPACING OF MANHOLES 



5.4.11 Cleanout Clearances 

Cleanouts on 3" or larger pipes shall be so installed that there is a clearance of not less than 18" for the 
purpose of rodding. Cleanouts smaller than 3 inches shall be so installed that there is a 12" clearance for 
rodding. See Figure 5.4.1 1-A and-B 



2006 National Standard Pumbing Code-Illustrated 



147 



PIPE SIZE "D" 




NOTES: 

1 . Minimum clearance "X" is 12" if pipe size "D" = 2" or less 

2. Minimum clearance "X" is 1 8" if pipe size "D" = 3" or more 

Figure 5.4.11 - A 
CLEANOUT CLEARANCE ABOVE THE BASE OF A STACK 



m^ov^mmL 



m 




NOTES: 
1. 
2. 



Minimum clearance "X" is 12" if pipe size "D" = 2" or less 
Minimum clearance "X" is 18" if pipe size "D" = 3" or more 

Figure 5.4.11 - B 
CLEANOUT CLEARANCE AT THE BASE OF A STACK 



5.4.12 Cleanouts to be Kept Uncovered 

Cleanout plugs shall not be covered with cement, plaster, or any other permanent finishing material. Where it 
is necessary to conceal a cleanout plug, a covering plate or access door shall be provided that will permit 
ready access to the plug. 

5.4.13 Cleanout Equivalent 

Where the piping is concealed, a fixture trap or a fixture with integral trap, readily removable without disturb- 
ing concealed roughing work, shall be accepted as a cleanout equivalent, provided the opening to be used as a 
cleanout opening is the size required by Table 5.4.9. 



148 



2006 National Standard Pumbing Code-Illustrated 



EXCEPTIONS: 

(1) The trap arm of a floor drain with a removable strainer. 

(2) Fixtures with readily removable traps not more than one pipe size smaller than the drain served shall 
be permitted. 

See Figure 5.4.13-A and-B 




Figure 5.4.13 - A 
A WATER CLOSET AS A CLEANOUT EQUIVALENT 



ro 



SLIP JOINT 




GROUND OR 
SLIP JOINT 



Figure 5.4.13 - B 
A REMOVABLE TRAP AS A CLEANOUT EQUIVALENT 



2006 National Standard Pumbing Code-Illustrated 



149 



5.4.14 Cleanouts for Floor Drains 

A cleanout shall be provided immediately downstream from a floor drain whose strainer is not readily remov- 
able. 

5.5 BACKWATER VALVES 

5.5.1 Where Required 

a. Fixtures and/or drain inlets subject to backflow and flooding from blocked or restricted public sewers 
shall be protected by a backwater valve. 

b. Such situations include those where fixtures and/or drains are located above the crown level of the public 
sewer at the point of connection thereto, but are below the level of the curb at the point where the building 
sewer crosses under the curb at the property line. 

c. Backwater valves shall be installed in branches of the drainage system that receive flow only from 
fixtures and/or drains subject to backflow from the public sewer. 

d. Other portions of the drainage system not subject to such backflow shall drain directly to the public 
sewer. 

5.5.2 Material Standard and Accessibility 

Backwater valves shall conform to ASME Al 12.14. 1 and be installed so that their internal working parts are 
accessible for periodic cleaning, repair or replacement. 

5.5.3 Notice of the Installation of Backwater Valves 

When backwater valves are installed in building sanitaiy drainage systems, a notice shall be posted at the 
building water service shutoff valve(s) describing where backwater valves are located. 



J 5Q 2006 National Standard Pumbing Code-Illustrated 



Liquid Waste Treatment Equipment 



6.1 GENERAL 



6.1.1 Where Required 

Interceptors, separators, neutralizers, dilution tanks, or other means shall be provided where required to 
prevent liquid wastes containing fats, oils, greases, flammable liquids, sand, solids, acid or alkaline waste, 
chemicals, or other harmful substances from entering a building drainage system, a public or private sewer, or 
sewage treatment plant or process. See Figure 6.1.1 



INLET 




OUTLET 



OUTLET 



REMOVABLE 
BASKET 




GREASE INTERCEPTOR 



SOLIDS INTERCEPTOR 



GRATE 



ACCESS 
COVER 



VENT 



1 


r~_ 


■ 




INLET 


tenii 


y=M' 


OUTLET 




-.'-.' -^ .;...-■■■■'"-■■■,.'".,■ ,-..'•; ■„ ■„,..■•> :.;.-. ■ 




s 


AND INTERCEPTO 


R 



INLET 



ADJUSTABLE 

OIL 

DRAWOFF 




OIL INTERCEPTOR 

Figure 6.1.1 
DIFFERENT TYPES OF INTERCEPTORS 

6.1.2 Design 

The size and type of liquid waste treatment equipment shall be based on the maximum volume and rate of 
discharge of the plumbing fixtures and equipment being drained. See Appendix J. 

6.1.3 Exclusion of Other Liquid Wastes 

Only wastes from fixtures and equipment requiring treatment or separation shall be discharged into treatment 
equipment. 



2006 National Standard Pumbing Code-Illustrated 



151 



6.1.4 Approval 

6.1.4.1 General 

The type, size, capacity, design, arrangement, construction, and installation of liquid waste treatment 
devices shall be as approved by the Authority Having Jurisdiction. 

6.1.4.2 Grease Interceptors and Grease Recovery Devices 

Grease interceptors rated for up to 100 gallons per minute shall be certified according to PDI Standard 
G101 or ASME Al 12.14.3. Grease recovery devices rated for up to 100 gallons per minute shall be 
certified according to ASME Al 12.14.4. 

6.1.4.3 Mechanical Equipment 

Each installation of a manufactured liquid waste treatment device employing pumps, filters, drums, 
collection plates, or other mechanical means of operation shall be certified by the manufacturer to 
provide effluent meeting the environmental requirements of the sewer or other approved point to which 
it discharges. 

6.1.5 Venting 

Liquid waste treatment equipment shall be so designed that they will not become air-bound if tight covers are 
used. Equipment shall be properly vented if loss of its trap seal is possible. 

6.1.6 Accessibility 

a. Liquid waste treatment equipment shall be so installed that it is accessible for the removal of covers and 
the performance of necessary cleaning, servicing and maintenance. 

b. The need to use ladders or move bulky objects in order to service interceptors and other liquid waste 
treatment equipment shall constitute a violation of accessibility. 

6.1.7 Point of Discharge 

Connections to sewers or other points of discharge for the effluent from liquid waste treatment equipment 
shall be as approved by the Authority Having Jurisdiction. 

6.2 GREASE INTERCEPTORS AND GREASE RECOVERY DEVICES (GRD) 

6.2.1 Sizes Up to 100 GPM 

a. Manufactured grease interceptors rated up to 1 00 gallons per minute shall comply with ASME Al 12. 14.3 
and be sized and installed in accordance with the recommendations of PDI Standard G 1 1 - Appendix A and the 
manufacturer's instructions. They shall have a grease retention capacity not less than two pounds for each gpm 
of rated flow. A flow control device shall be provided to prevent the waste flow (gpm) through the interceptor 
from exceeding its rated flow capacity. An air intake shall be provided for the flow control as recommended by 
the manufacturer or PDI Standard G101 - Appendix A. See Figure 6.2.1 for a flow control device 

b. Grease interceptors that include automatic grease recovery (GRD) shall comply with Section 6 2 1 a and 
ASME Al 12.14.4. 



1!1 

"* 2006 National Standard Pumbing Code-Illustrated 



PLUNGER FOR 
CLEANING ORIFICE 



INLET 



OUTLET 




PACKING GLAND 



VENT 
CONNECTION 



Figure 6.2.1 
A FLOW CONTROL DEVICE FOR A GREASE INTERCEPTOR 



6.2.2 Fixture Traps 

a. Fixtures that discharge into a grease interceptor shall be individually trapped and vented between the 
fixture and the interceptor. 

b. When individually trapped and vented fixtures discharge into a grease interceptor, the required vented 
flow control device shall be installed between the vented fixture traps and the interceptor. 

EXCEPTION: A grease interceptor with the required flow control device shall be permitted to serve as a trap 
for an individual fixture if the developed length of the drain between the fixture and the interceptor does not 
exceed four feet horizontally and 30 inches vertically. 
See Figure 6.2.2-A and-B 



2006 National Standard Pumbing Code-Illustrated 



153 



MULTIPLE SINK COMPARTMENTS 
WITH ONE OR MORE VENTED TRAPS 




AIR INTAKE FOR 

FLOW CONTROL DEVICE 

FIXTURE TRAP 
VENT(S) 



J 

FLOW 
, CONTROL I 
I DEVICE 



FIXTURE TRAP 




VENT TO 
ATMOSPHERE 



ACCESSIBLE GREASE INTERCEPTOR 
ABOVE OR BELOW FLOOR 



-WASTE DRAIN 



NOTES: 

1 . Flow control devices are necessary to prevent the waste flow from exceeding the design flow rating 
of the grease interceptor. 

2. When the fixtures connected to the grease interceptor have traps, the air intake on the flow control 
device must be connected to the fixture vent piping system. 

3. Air intake through the flow control device aerates the grease-laden waste, which is essential to the 
separation process. 



Figure 6.2.2 - A 



A GREASE INTERCEPTOR SERVING TRAPPED AND VENTED FIXTURES 



SINK OR DISHWASHER 
FIXTURE OVERFLOW LEVEL 




VENT TO 
ATMOSPHERE 



ACCESSIBLE GREASE INTERCEPTOR 
ABOVE OR BELOW FLOOR 



WASTE DRAIN 



NOTES: 

1 . When a fixture that is connected to a grease interceptor is within 4 feet horizontally and 30 inches 
vertically from the inlet to the interceptor, a fixture trap is not required. If the fixture is not trapped, 
the air intake for the flow control device must not be connected to the vent piping system. It must 
be terminated at a 180 degree return bend with its inlet at least 6 inches above the flood level of the 
fixture. 

Figure 6.2.2 - B 
A GREASE INTERCEPTOR SERVING AS A FIXTURE TRAP 



154 



2006 National Standard Pumbing Code-Illustrated 



6.2.3 Food Waste Grinders 

Where food waste grinders discharge through a grease interceptor, a solids interceptor shall be installed 
upstream of the grease interceptor to prevent food particles from entering the grease interceptor See 
Figure 6.2.3 



AIR INTAKE FOR 

FLOW CONTROL DEVICE 



FIXTURE TRAP 
VENT 



SINK- 



FOOD WASTE - 
GRINDER 



^_^ 



SOLIDS SEPARATOR 




VENT TO 
ATMOSPHERE 



ACCESSIBLE GREASE INTERCEPTOR 
ABOVE OR BELOW FLOOR 



WASTE DRAIN 



Figure 6.2.3 
A FOOD WASTE GRINDER WITH SOLIDS SEPARATOR AND GREASE INTERCEPTOR 

6.2.4 Commercial Dishwashers 

Commercial dishwashers shall be permitted to discharge through a grease interceptor. 

6.2.5 Location 

Grease interceptors shall be permitted to be installed within buildings unless otherwise prohibited by the 
Authority Having Jurisdiction. Where interceptors or holding tanks are remote from the fixtures served, the 
drain piping between the fixtures and the interceptor or holding tank shall be as direct as possible and shall 
include provisions for periodic cleaning. 

6.2.6 Prohibited Interceptors 

The installation of water-cooled grease interceptors shall be prohibited. 

6.2.7 Chemicals Prohibited 

The use of enzymes, emulsifiers, or similar chemicals in grease interceptors shall be prohibited. 

6.2.8 Individual Dwelling Units 

Grease interceptors shall not be required in individual dwelling units or any private living quarters. 



2006 National Standard Pumbing Code-Illustrated 



155 



6.3 OIL/WATER SEPARATORS 

6.3.1 Where Required and Approved Point of Discharge 

a. Liquid waste containing grease, oil, solvents, or flammable liquids shall not be directly discharged into 
any sanitary sewer, storm sewer, or other point of disposal. Such contaminants shall be removed by an 
appropriate separator. 

b. Sand interceptors and oil separators shall be provided wherever floors, pits or surface areas subject to 
accumulation of grease or oil from service or repair operations are drained or washed into a drainage system. 
Such locations include, but are not limited to, car or truck washing facilities, engine cleaning facilities, and 
similar operations. The drainage or effluent from such locations shall be connected to the sanitary sewer. 

c. Drains shall not be required in service or repair garages that employ dry absorbent cleaning methods; 
however, if any drains are located in such areas, they shall discharge to the sanitary sewer through a sand 
interceptor and oil interceptor. 

d. Drains shall not be required in parking garages unless the garage, or portions thereof, has provisions for 
either washing vehicles or rinsing the floor. Where such cleaning facilities are provided, the area subject to 
waste drainage shall be provided with one or more floor drains, complete with sand interceptor and oil inter- 
ceptor, and the effluent from the oil separator shall be connected to the sanitary sewer. Any storm water shall 
be drained separately and directly to the storm sewer. 

e. Where parking garages without provisions for vehicle washing or floor rinsing require storm water 
drainage, drains shall be permitted to connect to the storm sewer without a sand interceptor and oil separator. 
Such drainage, including melting snow, ice or rainwater runoff from vehicles, shall not be connected to the 
sanitary sewer. 

f. Where oil separators include a waste holding tank, it shall not be used to store or contain any other 
waste oil (e.g., motor oil) or hazardous fluid. 

6.3.2 Design of Oil Separators 

a. Where oil separators are required in garages and service stations, they shall have a minimum volume of 
six cubic feet for the first 100 square feet of area drained, plus one cubic foot for each additional 100 square 
feet of area drained. Oil separators in other applications shall be sized according to the manufacturers rated 
flow. 

b. Field-fabricated oil separators shall have a depth of not less than two feet below the invert of the 
discharge outlet. The outlet opening shall have a water seal depth of not less than 18 inches. 

c. Manufactured oil separators shall be sized according to gallons per minute of rated flow. They shall 
include a flow control device and adjustable oil draw-off. 

d. Oil separators shall have a 3-inch minimum discharge line and a 2-inch minimum vent to atmosphere. 
The discharge line shall have a full-size cleanout extended to grade or otherwise be accessible. 

e. The oil draw-off or overflow piping from oil separators shall be connected to an approved waste oil tank 
that is installed and permitted according to the environmental requirements of the Authority Having Jurisdic- 
tion. The waste oil from the separator shall flow by gravity or may be pumped to a higher elevation by an 
automatic pump. Pumps shall be adequately sized, explosion-proof, and accessible. Waste oil tanks shall have 
a 2-inch minimum pump-out connection and a 1-1/2 inch minimum vent to atmosphere. 

f. Where oil separators are subject to backflow from a sewer or other point of disposal, their discharge 
line shall include a backwater valve, installed in accordance with Section 5.5. 

g. Where oil separators are installed in parking garages and other areas where the waste flow will include 
sand, dirt or similar soilds, a sand interceptor shall be provided upstream from the oil separator. Sand intercep- 
tors shall comply with Section 6.4. 

h. Oil interceptors, waste oil tanks, oil pump-out connections, backwater valves and atmospheric vent 
piping shall be permanently identified by suitable labels or markings. 



156 2006 National Standard Pumbing Code-Illustrated 



6.3.3 Vapor Venting 

The atmospheric vents from oil separators and their waste holding tanks shall be separate from other plumb- 
ing system vents and shall be extended to an approved location at least 12 feet above grade or the surround- 
ing area. 

6.3.4 Combination Oil Separator and Sand Separator 

A combination oil separator and sand separator meeting the functional requirements of Sections 6.3 and 6.4 
shall be permitted to be installed. 

6.4 SAND INTERCEPTORS 

6.4.1 Where Required 

a. A sand interceptor shall be installed upstream from an oil separator if required in Section 6.3.2.g. 

b. A sand interceptor shall be provided downstream from any drain whose discharge may contain sand, 
sediment, or similar matter on a continuing basis that would tend to settle and obstruct the piping in the 
drainage system. Multiple floor drains shall be permitted to discharge through one sand interceptor. 

6.4.2 Construction and Size 

a. Sand interceptors shall be constructed of concrete, brick, fabricated coated steel, or other watertight 
material, and shall be internally baffled to provide an inlet section for the accumulation of sediment and a 
separate outlet section. 

b. The outlet pipe of a sand interceptor shall be the same size as the drain served. 

EXCEPTION: If serving an oil separator, the outlet from the sand interceptor shall be the same size as the 
inlet to the oil separator. 

c. The inlet baffle shall have two top skimming openings, each the same size as the outlet pipe and at the 
same invert as the outlet opening. The openings in the baffle shall be offset to prevent straight-line flow 
through the interceptor from any of its inlets to its outlet. 

d. The inlet to the interceptor shall be at the same elevation as, or higher than, the outlet. The bottom of 
the inlet section shall be at least 24 inches below the invert of the outlet pipe. 

e. The bottom of the inlet section shall be at least two feet wide and two feet long for flow rates up to 20 
gallons per minute. The bottom of the inlet section shall be increased by one square foot for each 5 gpm of 
flow or fraction thereof over 20 gpm. The bottom of the outlet section shall be not less than 50% of the area 
of the bottom of the inlet section. 

f. A solid removable cover shall cover the outlet section. An open grating suitable for the traffic in the 
area in which it is located shall cover the inlet section. Covers shall be set flush with the finished floor. 
See Figures 6.4.2-A and-B 



2006 National Standard Pumbing Code-Illustrated 157 



GRATE- 



Q™ 



INLET SLIGHTLY 
HIGHER THAN 
OUTLET 



SOLID ACCESS COVER- 



7 



GRADE OR 
■ FLOOR LINE 



STAGGERED FLOW 
OPENINGS - 



m 

24" 

US 



24" MIN. 



:SEDIMENTr 



7 ~2 TO OIL/WATER SEPARATOR 



-WATERPROOFING 



INLET SECTION - 



-OUTLET SECTION 



SECTION VIEW 

NOTES: 

1 . Where a sand interceptor is installed upstream from an oil separator, the sand interceptor does not 

have to include a 6" trap seal depth. The oil separator provides the trap seal that blocks the flow of 

sewer gas from the building sewer into the building. 

Figure 6.4.2 - A 
A SAND INTERCEPTOR SERVING AN OIL SEPARATOR 



GRATE AND 
ACCESS COVER 
REMOVED 




GRATE- 



PLAN VIEW 



SOLID REMOVABLE 
COVER 



INVERT OF OUTLET - 



TiNI 



EPSSSSES 



7 r 



GRADE OR 
FLOOR LINE 



INLET SI 



m 



E 24" MINjL^SEDIMENT" 



e=3j! 



STAGGERED TOP 

SKIMMING OPENINGS / I WA 



t^-6" MINIMUM TRAP SEAL 



m 



3 OUTLET 



INLET SECTION 



zr 



-WATERPROOFING 



-OUTLET SECTION 



SECTION VIEW 



NOTES: 

1 . Where a stand-alone sand interceptor is installed, it must include a 6" trap seal depth to block the 
flow of sewer gas from the building sewer into the building. 

Figure 6.4.2 - B 
A STAND-ALONE SAND INTERCEPTOR 



158 



2006 National Standard Pumbing Code-Illustrated 



6.4.3 Water Seal 

When a sand interceptor is used separately without also discharging through an oil separator, its outlet pipe 
shall be turned down inside the separator below the water level to provide a six-inch minimum water seal. A 
cleanout shall be provided for the outlet line. 

6.4.4 Alternate Design 

Alternate designs for construction of, or baffling in, sand interceptors shall comply with the intent of this Code 
and be submitted to the Authority Having Jurisdiction for approval. 

6.5 SOLIDS INTERCEPTORS 

a. Solids interceptors shall be provided where necessary to prevent harmful solid materials from entering the 
drainage system on a continuing basis. Such harmful materials include, but are not limited to, aquarium gravel, 
barium, ceramic chips, clay, cotton, denture grindings, dental silver, fish scales, gauze, glass particles, hair, jewels, 
lint, metal grindings, plaster, plastic grindings, precious metal chips, sediment, small stones, and solid food particles. 

b. Solids interceptors shall separate solids by gravity, trapping them in a removable bucket or strainer. 

c. Solids interceptors shall be sized according to their drain pipe size or by the required flow rate. 

6.6 NEUTRALIZING AND DILUTION TANKS 

a. Neutralizing or dilution tanks shall be provided where necessary to prevent acidic or alkaline waste from 
entering the building drainage system. Such waste shall be neutralized or diluted to levels that are safe for the 
piping in the drainage and sewer systems. 

b. Vents for neutralizing or dilution tanks shall be constructed of acid-resistant piping and shall be independent 
from sanitary system vents. 

6.7 SPECIAL APPLICATIONS 

6.7.1 Laundries 

Commercial laundries shall be equipped with one or more lint interceptors having wire baskets or similar 
devices, removable for cleaning, that will prevent passage into the drainage system of solids 1/2 inch or larger 
in size, strings, rags, buttons, lint, and other materials that would be detrimental to the drainage system. 

6.7.2 Bottling Establishments 

Bottling plants shall discharge their process wastes into a solids separator that will retain broken glass and 
other solids, before discharging liquid wastes into the drainage system. 

6.7.3 Slaughter Houses 

Drains in slaughtering rooms and dressing rooms shall be equipped with separators or interceptors, approved 
by the Authority Having Jurisdiction, that will prevent the discharge into the drainage system of feathers, 
entrails, and other waste materials that are likely to clog the drainage system. 

6.7.4 Barber Shops and Beauty Parlors 

Shampoo sinks in barbershops, beauty parlors, and other grooming facilities shall have hair interceptors 
installed in lieu of regular traps. 



2006 National Standard Pumbing Code-Illustrated 159 



Blank Page 



1 "" 2006 National Standard Pumbing Code-Illustrated 






""s**™ 8 ^^ ■■ — ip 

Plumbing Fixtures, Fixture Fittings and 
Plumbing Appliances 



7.1 FIXTURE STANDARDS 

Plumbing fixtures, plumbing fixture trim, and plumbing appliances shall comply with the standards listed in Table 

7.2 FIXTURES FOR ACCESSIBLE USE 

Plumbing fixtures for accessible use and their installation shall confirm to the requirements of the Authority Having 
Jurisdiction. t: 

7.3 INSTALLATION 

7.3.1 General 

Plumbing fixtures, fixture trim, and plumbing appliances shall be installed in accordance with the requirements 
of this Code and the manufacturer's instructions and recommendations. 

7.3.2 Minimum Clearances 

For other than accessible applications, minimum clearances between plumbing fixtures and from fixtures to 
adjacent walls shall be in accordance with Figure 7.3.2. 

7.3.3 Access for Cleaning 

Plumbing fixtures shall be so installed as to provide access for cleaning the fixture and the surrounding area. 

7.3.4 SecuringFloor-Mounted Fixtures 

Floor-mounted fixtures shall be securely supported by the floor or floor/wall structure. No strain shall be 
transmitted to the connecting piping. Fastening screws or bolts shall be corrosion-resisting. 



2006 National Standard Plumbing Code-Illustrated 1fi1 



mm^mmm^mm. 




30" 
CLEAR 



y/////f^///////////////, 



60" 

CLEAR 

L 



•mmm 



COMPART- 
MENT 



WALL 



A E" 



OTHER BUILDINGS 
DWELLINGS 



21" 
CLEARANCE 



WATER CLOSETS 
OR BIDETS 




WALL 



^^^mw////////M». 



— I 15" I— 



[— 30" -— | I— 30" — | 

. H II II 




1 




WALL I 

/ 



21" 
CLEARANCE 




W.C. 



URINALS 





LAVATORIES 




The clear height between ceilings and 

floors shall comply to the requirement of 

the Building Code. 



SHOWERS 



24" CLEARENCE IN FRONT OF OPENING 



Figure 7.3.2 
MINIMUM FIXTURE CLEARANCES 



162 



2006 National Standard Plumbing Code-Illustrated 



7.3.5 Supporting Wall-Hung Fixtures 

a. Wall-hung water closets shall be supported by concealed metal carriers that transmit the entire weight 
of the fixture to the floor and place no strain on the wall or connecting piping. Supports of this design shall 
comply with ASME Al 12.6.1 . 

b. Free-standing lavatories, wall-hung urinals, water closets with or without concealed tanks and other 
wall-mounted fixtures shall be supported by a concealed or exposed finished wall hanger plate or equivalent 
that transmits the weight of the fixture to the wall structure, if adequate, or to the floor without placing strain 
on the piping. Such supports shall comply with ASME A 1 12.6.2 or ASME Al 12.19.12. In addition to the wall 
support brackets, pedestals or legs may provide additional support for pedestal lavatories. 

See Figure 7.3.5 



WALL 



CARRIER BODY 



-SUPPORT IS ENTIRELY ON 
CARRIER BOLTS 




LAG SCREW AND ANCHOR 



NOTES: 

1 . Wall hung water closets are designed to be supported by carriers. 

2. For fixtures other than water closets, such as lavatories and urinals, the carrier may be either floor 
or wall supported, depending on the strength of the wall. 

Figure 7.3.5 
A CARRIER FOR A WALL HUNG WATER CLOSET 



7.3.6 Orientation and Operation of Faucets 

Where fixtures are supplied with both hot and cold water, the faucet(s) and supply piping shall be installed so 
that the hot water is controlled from the left side of the fixture or faucet when facing the controls during 
fixture use. 

EXCEPTION: Single handle and single control valves for showers and tub/shower combinations where the 
hot and cold temperature orientation is marked on the fitting surface. 

7.3.7 Access to Concealed Connections 

Where fixtures have drains with concealed slip joint connections or incorporate a cleanout plug, a means of 
access shall be provided for inspection and repair. Such access is not required for connections that are 
soldered, threaded, solvent cemented, or equivalently secured. 



Comment: Access to concealed slip joints and cleanouts can require the use of tools. 



2006 National Standard Plumbing Code-Illustrated 



163 



7.3.8 
Joints 
7.3.8 



Joints with Walls and Floors 
where fixtures contact walls and floors shall be caulked or otherwise made water-tight. See Figure 



1 

1 

z 

% 




SEAL EDGES 
AND SIDES 




^- ESCUTCHEON 
LAVATORY 



-SEAL EDGES 
AND SIDES 




- SEAL EDGES 



-m^^^w^; 




SEAL EDGES 
AROUND BASE 



^R^J^^^^ 



WALL HUNG WATER CLOSET 



FLOOR MOUNTED WATER CLOSET 



V^ 



E 



SEAL 
EDGES 
AND AT 



^\\-\\\x\^^\^\^\^^^\^ FLOOR ^ ^^ ^^^^^^^^^ 



-SEAL EDGES 
.AND SIDES 




SHOWER STALL 



BATHTUB 



NOTES: 

1 . Openings or gaps between fixtures and walls or floors can collect dirt and moisture. They are 
unsanitary and can cause water damage to the building structure. These openings must be caulked 
or otherwise sealed. 

Figure 7.3.8 
SEALING FIXTURES TO WALLS AND FLOORS 



7.4 WATER CLOSETS 

7.4.1 Compliance 

Vitreous china water closets shall comply with ASME Al 12.19.2M. Plastic water closets shall comply with 
ANSI Z 124.4. 

7.4.2 Water Conservation 

Water closets, whether operated by flush tank, flushometer tank, or flushometer valve, shall comply with 
ASME Al 12.19.2M and shall be the low-consumption type having an average consumption of not more than 
1 .6 gallons per flush when tested in accordance with ASME A 1 12. 1 9.6. 
EXCEPTION: Blow-out water closets and clinical sinks. 



164 



2006 National Standard Plumbing Code-Illustrated 



7.4.3 Contour of Bowls 

Water closets shall have elongated bowls with open-front seats. 
EXCEPTIONS: 

(1) Water closets having closed-front seats and either round or elongated bowls shall be permitted in 
dwelling units. 

(2) Water closets having closed-front seats that are protected by automated seat cover protection. 

(3) A water closet in a private office toilet room, intended for the exclusive use of one individual. 

(4) Water closets intended for use in pre-school and kindergarten facilities. 
See Figure 7.4.3-A and-B 



REGULAR BOWL 




ELONGATED 
BOWL 

RIM 



13 1/2" MINIMUM 

(SEE EXCEPTIONS IN 

FIGURES 7.4.4-A and 

7.4.4-B) 



NOTES: 

1 . See Figure 7.4.4 - A for bowl heights for children's use. 

2. See Figure 7.4.4 - B for bowl heights for adult accessible use. 

Figure 7.4.3 - A 

AN ADULT-HEIGHT ELONGATED WATER CLOSET BOWL 

COMPARED TO A ROUND BOWL 




NOTES: 

1 . Seats for water closets must fit the water closet bowl. Section 7.4.5 requires elongated seats on 
elongated bowls and round seats on round bowls. 

Figure 7.4.3 - B 
AN OPEN FRONT ELONGATED WATER CLOSET SEAT (LESS LID) 



2006 National Standard Plumbing Code-Illustrated 



165 



7.4.4 Bowl Height 

The height of water closet bowls shall be a minimum of 13!4 inches from the floor to the top of the rim. 
EXCEPTIONS: 

(1) Bowls intended for children's use (5 years and younger) are permitted to be 9-1/2" to 10-1/2" high to the 
rim and juvenile use (6-12 years) are permitted to be 10-1/2" to 13-1/2" high to the rim. 

(2) The height of bowls intended specifically for children' s accessible use ( 1 2 years and younger) shall be such 
that the top of the seat is 11" to 17" above the floor and comply with Section 7.2. 

(3) The height of bowls intended specifically for adult accessible use (13 years and older) shall be such that 
the top of the seat is 17" to 19" above the floor and comply with Section 7.2. 

See Figures 7.4.3-A, 7.4.4-A, and 7.4.4-B. 



APPLICATION 


AGE - YEARS 


HEIGHT "H" 


CHILDREN'S USE 


5 & YOUNGER 


9-1/2" TO 10-1/2" TO RIM 


JUVENILE (CHILDREN'S) USE 


6-12 


10-1/2" TO 13-1/2" TO RIM 


ACCESSIBLE CHILDREN'S USE 


12 & YOUNGER 


1 1" TO 1 7" TO TOP OF SEAT 




^^^m^////////////////////////m////////A 



Figure 7.4.4 - A 
PERMITTED HEIGHTS OF WATER CLOSET BOWLS FOR CHILDREN'S USE 



17" - 19" 




TOP OF SEAT 



mmzmmmzmmzmmzmmWs 



Figure 7.4.4 - B 
PERMITTED HEIGHT OF WATER CLOSET BOWLS FOR ADULT ACCESSIBLE USE 



166 



2006 National Standard Plumbing Code-Illustrated 



7.4.5 Water Closet Seats 

Seats for water closets shall be of smooth, non-absorbent materials, be properly sized to fit the water closet 

bowl, and comply with ANSI Z 124.5 

EXCEPTION: Water closet seats in dwelling units are not required to comply with ANSI Z124.5. 

7.4.6 Hotels, Motels, Dormitories, and Boarding Houses 

Water closets in hotels, motels, dormitories, boarding houses and similar occupancies shall be the elongated 
type complying with ASME Al 12.19.2 or ANSI Z 124.4, and ASME Al 12.19.6 and with open-front seats 
complying with ANSI Z 1 24.5 
EXCEPTIONS: 

(1) Closed-front seats shall be permitted in hotel and motel guest rooms. 

(2) Closed-front seats that are provided with automatic seat cover protection. 

7.4.7 Prohibited Water Closets 

Water closets not having a visible trap seal or having either unventilated spaces or walls that are not washed 
at each discharge shall be prohibited. 

7.4.8 Macerating Toilet Systems 

Macerating toilet systems and related components shall comply with ASME Al 12.3.4 or CSA B45.9. 

7.5 URINALS 

7.5.1 Compliance 

a. Urinals with a non-visible water trap seal and/or strainer shall be equipped with an automatic flushing 

device. 

b. Vitreous china urinals shall comply with ASME A 1 1 2. 1 9.2. 

c. Plastic urinals, including female urinals, urinals for the physically impaired, and waterless male urinals, 
shall comply with ANSI Z 124.9. 

7.5.2 Water Conservation 

Water-fed urinals shall be the low-consumption type having an average water consumption of not more than 
1 .0 gallon per flush when tested in accordance with ASME A 1 12.9.6. 

7.5.3 Surrounding Surfaces 

Urinals shall not be installed where wall and floor surfaces are not waterproof and do not have a smooth, 
readily cleanable, non-absorbent surface extending not less than four feet above the floor and one foot to 
each side of the urinal, and one foot in front of the lip of the urinal. See Figure 7.5.3. 

7.5.4 Prohibited Urinals 

Trough urinals and urinals having walls that are not washed at each discharge shall be prohibited. 
EXCEPTION: Waterless urinals complying with ANSI Z 1 24.9. 



2006 National Standard Plumbing Code-Illustrated -t£.~i 



r-o" 



v-or 



AREA THAT 
MUST BE 
COVERED WITH 
A WATERPROOF 
MATERIAL 





X PLUS 12" 

X EQUALS THE DEPTH OF THE URINAL 



Figure 7.5.3 
PROTECTING SURROUNDING SURFACES AT URINALS 



7.6 LAVATORIES 



7.6.1 Compliance 

a. Lavatories shall comply with the following standards: 

1. Ceramic, non-vitreous; ASME Al 12.19.9M 

2. Enameled cast-iron; ASME Al 12.19.1M 

3. Enameled steel; ASME A112.19.4M 

4. Plastic; ANSI Z 124.3 

5. Stainless steel; ASME Al 12.19.3M 

6. Vitreous china; ASME Al 12. 19.2M 

7.6.2 Water Conservation 

a. Except as required under Section 7.6. 2. c, lavatory faucets shall be designed and manufactured so that 
they will not exceed a water flow rate of 2.2 gallons per minute when tested in accordance with ASME 
Al 12.18.1. 

b. Public lavatory faucets, other than the metering type, shall be designed and manufactured according to 
ASME Al 12.18.1. 

c. Self-closing or self-closing/metering faucets shall be installed on lavatories intended to serve the 
transient public, such as those in, but not limited to, service stations, train stations, airport terminals, restau- 
rants, and convention halls. Metering faucets shall deliver not more than 0.25 gallon of water per use when 
tested in accordance with ASME All 2. 18.1. Self-closing faucets shall be designed and manufactured so 
that they will not exceed a water flow rate of 0.5 gallon per minute when tested in accordance with ASME 
A112.18.1. 



168 



2006 National Standard Plumbing Code-Illustrated 



7.6.3 Waste Outlet 

The waste outlet pipe on individual lavatories shall be not less than 1-1/4" nominal size. A strainer, pop-up 
stopper, crossbar grid, or other device shall be provided to protect the waste outlet. 

7.6.4 Integral Overflow 

Where lavatories include an integral overflow drain, the waste fitting shall be designed and installed so that 
standing water in the bowl of the fixture cannot rise in the overflow channel when the drain is closed, nor 
shall any water remain in the overflow channel when the bowl is empty. The overflow shall drain to the inlet 
side of the fixture trap. See Figure 7.6.4 



Comment: Overflows are not provided in all lavatories. Lavatories with overflows are not used in 
hospitals because of the potentially unsanitary condition caused by inaccessible surfaces exposed to 
waste. 



OVERFLOW OPENING 
(WHERE PROVIDED) - 



ezz7p^j 



(JZ3ZZZZ3 




OVERFLOW TO DISCHARGE INTO 
FIXTURE SIDE OF TRAP 



POP-UP LEVER 



Figure 7.6.4 
A LAVATORY OVERFLOW 



7.6.5 Lavatory Equivalent 

Where group-type wash fountains or wash sinks are used to satisfy the number of lavatories required by 
7.21.1, each 1 8-inch usable length of rim having an available water spray shall be considered as one lavatory. 
See Figure 7.6.5 



2006 National Standard Plumbing Code-Illustrated 



169 




EACH 18" IS EQUIVALENT 
TO 1 LAVATORY 



RECEIVING 
BASIN 



SPRAY 
HEAD 




PLAN 



ELEVATION 



Figure 7.6.5 
A CIRCULAR WASH FOUNTAIN 



7.7 BIDETS 



7.7.1 Compliance 

Vitreous china bidets shall comply with ASME Al 12.19.2M. Bidet faucets shall comply to ASME 
A112.18.1. 

7.7.2 Backflow Prevention 

Bidets having integral flushing rims shall have a vacuum breaker assembly on the mixed water supply to the 
fixture. Bidets without flushing rims shall have an over-the-rim supply fitting providing the air gap required by 
Chapter 10. 

7.7.3 Integral Overflow 

Where bidets include an integral overflow drain, the waste fitting shall be designed and installed so that 
standing water in the bowl of the fixture cannot rise in the overflow channel when the drain is closed, nor 
shall any water remain in the overflow channel when the bowl is empty. The overflow shall drain to the inlet 
side of the fixture trap. 

7.8 BATHTUBS 

7.8.1 Compliance 

a. Bathtubs shall comply with the following standards: 

1. Plastic, cultured marble and other synthetic products or finishes; ANSI Z 124.1 

2. Enameled cast-iron; ASME Al 12.19.1 

3. Enameled steel; ASME Al 12. 1 9.4 

4. Bathtubs with pressure sealed doors; ASME Al 12.19.15 

7.8.2 Waste and Overflow 

Bathtubs shall have waste outlet and overflow pipes not less than 1-1/2" nominal size. Waste outlets shall be 
equipped with a pop-up waste, chain and stopper, or other type of drain plug. See Figure 7.8.2 



170 



2006 National Standard Plumbing Code-Illustrated 




TRIP LEVER 



OVERFLOW TO DISCHARGE INTO 
FIXTURE SIDE OF TRAP 



P0P4JP WASTE SHOWN 



FLOW K--J-- 



Figure 7.8.2 
A BATHTUB WASTE AND OVERFLOW 

7.8.3 Combination Bath/Showers 

Shower heads, including the hand-held type, shall be designed and manufactured so that they will not exceed 
a water supply flow rate of 2.5 gallons per minute when tested in accordance with ASME All 2. 18.1. The 
control of mixed water temperatures to bath/shower combinations shall comply with Section 10.15.6. Sur- 
rounding wall construction shall be in accordance with Section 7. 10.5. e. Riser pipes to shower heads shall be 
secured in accordance with Section 7.10.7. 

7.8.4 Backflow Prevention 

Unless equipped with an atmospheric backflow preventer in accordance with ASSE 1001 or ASME 

A 11 2. 18.7, the bathtub filler shall be equipped with an air gap between the end of the over-rim tub filler spout 

and the overflow rim of the tub that complies with Section 10.5. 



7.9 WHIRLPOOL BATHS 

7.9.1 General 

The requirements of Section 7.8 for bathtubs shall also apply to whirlpool baths. The provisions for wet 
venting in Section 12.10 shall also apply to whirlpool baths. 

7.9.2 Compliance 

Whirlpool bathtubs shall comply with ASME A 1 1 2 . 1 9 .7M. 

7.9.3 Drainage 

The arrangements of circulating piping and pumps shall not be altered in any way that would prevent the 
pump and associated piping from draining after each use of the fixture. 

7.9.4 Access 

One or more removable panels shall be provided where required for access to pumps, heaters, and controls, 
as recommended by the fixture manufacturer. See Figure 7.9.4 



2006 National Standard Plumbing Code-Illustrated 



171 




ACCESS REQUIRED 
AS RECOMMENDED 
BY THE MANUFACTURER 



-T~7 /////////// y-y-y-y-y 



NOTES: 

1 . Access must be provided to electrical and plumbing components of whirlpool baths as recom- 
mended by the manufacturer. Refer to manufacturer's installation instructions. 

Figure 7.9.4 
ACCESS REQUIREMENTS FOR A WHIRLPOOL BATH 

7.10 SHOWERS 

7.10.1 Compliance 

Plastic shower receptors and stalls shall comply with ANSI Z124.2. 

7.10.2 Water Conservation 

Shower heads shall be designed and manufactured so that they will not exceed the flow rate for shower head 
specified in ASME Al 12. 18. 1M. 
EXCEPTION: Emergency safety showers. 

7.10.3 Control of Mixed Water Temperature 

The control of mixed water temperatures shall comply with Section 10.15.6. 

7.10.4 Shower Waste Outlet 

a. For a shower with a single shower head, the waste outlet connection shall be not less than 1-1/2" inches 
nominal size and for a shower with multiple shower heads shall be not less than 2 inches nominal size and 
have a removable strainer not less than 3 inches in diameter with %" minimum openings. 
EXCEPTIONS: 

(1) Bathubs with overhead showers. 

(2) Waste outlets shall be securely connected to the drainage system. 

(3) In group showers where each shower space is not provided with an individual waste outlet, the waste 
outlet(s) shall be so located and the floor so pitched that waste water from one outlet does not flow over the 
floor area serving another outlet. 

7.10.5 Shower Compartments 

a. The minimum outside rough-in dimension for shower bases and prefabricated shower compartments 
shall be 32 inches, 

b. The minimum rough-in depth for prefabricated tub/shower combinations shall be 30 inches. 

c. Where shower compartments have glass enclosures or field-constructed tile walls, the compartment 
shall provide clearance for a 30 inch diameter circle with the door closed. 

d. The minimum rough-in depth for shower compartments that replace existing bathtubs shall be no less 
than the rough-in depth of the bathtub that they replace. Such enclosures shall provide not less than 900 
square inches of inside clear floor area, 

e. The walls in shower compartments and above built-in bathtubs having installed shower heads shall be 
constructed of smooth, non-corrosive, non-absorbent waterproof materials that extend to a height of not less 



172 2006 National Standard Plumbing Code-illustrated 



than 68 inches above the fixture drain, 
f. The joints between walls and with bathtubs and shower compartment floors shall be water-tight. 

7.10.6 Shower Floors or Receptors 

a. Floors or receptors for shower compartments shall be laid on or be supported by a smooth and structur- 
ally sound base. 

b. Shower pans shall be provided under the floors of shower compartments. 

EXCEPTION: Shower pans shall not be required when prefabricated shower receptors are used. 

c. Shower pans shall form a watertight lining beneath the shower floor. 

d. Shower pans shall rum up at least 2 inches above the finished threshold level on all sides. 

e. Shower pans shall be securely fastened to the shower waste outlet at the seepage entrance, making a 
watertight joint between the pan and the waste outlet. 

f. Finished shower floor surfaces shall be smooth, non-corrosive, non-absorbent, and waterproof. 

See Figure 7.10.6 

WATERPROOF MEMBRANE AT LEAST 2" 
MINIMUM ABOVE THRESHOLD HEIGHT 




-FLUSH WITH FINISHED SURFACE 



FINISHED SURFACE 
GRADED TO DRAIN 



WEEP HOLES FOR 
SECONDARY DRAINAGE 



CLAMPING RING 




WATERPROOF PAN OR LINER 
UNDER CLAMPING RING 



Figure 7.10.6 
A SHOWER PAN AND DRAIN 

7.10.7 Water Supply Riser 

Whether exposed or concealed, the water supply riser pipe from the shower control valve(s) to the shower 
head outlet shall be secured to the wall structure. See Figure 7.10.7 



2006 National Standard Plumbing Code-Illustrated 



173 



SECURELY SUPPORTED 
WITH DROP EAR ELL 



ALTERNATE 
ARRANGEMENT 



TO SHOWER VALVE 

VALVE 

BODY 




ALTERNATE 

BLOCKING 

LOCATIONS 



*it^r 



I 



WATERPROOF 
WALL (Section 7.10.5) 



SHOWER CONTROL VALVE 



~^>- SEALED (Section 7.3.8) 



T 



AIR GAP 



JL. 



TOP OF BATHTUB 



SEALED 
(Section 7.3.8) 



Figure 7.10.7 
A SHOWER HEAD SUPPLY RISER PIPE 



7.11 SINKS 



7.11.1 Compliance 

a. Sinks shall comply with the following standards: 

1. Enameled cast-iron; ASME Al 12.19.1M 

2. Enameled steel; ASME Al 12.19.4M 

3. Stainless steel; ASME Al 12.19.3M 

4. Plastic; ANSI Z 124.6. 

7.11.2 Kitchen Sinks and Bar Sinks 

a. Each compartment in a kitchen sink or bar sink shall have an outlet suitable for either a domestic food 
waste grinder or a basket strainer. The waste outlet pipe for each compartment shall be 1-1/2" nominal size. 
Outlet fittings shall have crossbars or other provisions for protecting the drain outlet and shall include a means 
of closing the drain outlet. 

b. Faucets for kitchen sinks and bar sinks shall be designed and manufactured so that they will not exceed 
a water flow rate of 2.2 gallons per minute when tested in accordance with ASME Al 12.18. 1M. 

See Figure 7.11.2 



174 



2006 National Standard Plumbing Code-Illustrated 



BASKET STRAINER 



CONTINUOUS 

WASTE 

ASSEMBLY 



30" MAXIMUM 
FOR ONE TRAP 




DOMESTIC FOOD 
WASTE GRINDER 



TRAP 



Figure 7.11.2 
KITCHEN SINK DRAIN OUTLETS 



7.11.3 Laundry Sinks 

a. Sinks for laundry use shall be not less than 12 inches deep with a strainer and waste outlet connection not 
less than 1-1/2" nominal size. 

b. Utility faucets for laundry sinks shall comply with ASME Al 12. 1 8. 1 . 

7.11.4 Service Sinks and Mop Receptors 

a. Service sinks and mop receptors shall have removable strainers and waste outlet connections not less 
than 2" nominal size. 

b. Service sinks and mop receptors shall not be installed where walls and floors are not wateiproof and do 
not have a smooth, readily cleanable surface at least one foot in front of the sink or receptor, at least one foot 
on each side, and up to a point one foot above the faucet height. 

7.11.5 Sink Faucets 

a. Sink faucets having a hose thread or other means of attaching a hose to the outlet shall be protected 
from back-siphonage by either an integral vacuum breaker, an atmospheric vacuum breaker attached to the 
outlet, or pressure-type vacuum breakers on the fixture supply lines. 

b. Faucets for kitchen sinks shall be designed and manufactured so that they will not exceed the flow rate 
for kitchen faucet specified in ASME Al 12.18.1M. 

7.12 DRINKING FOUNTAINS AND WATER COOLERS 

7.12.1 Compliance 

Refrigerated drinking fountains and water coolers shall comply with ARI 1010 and UL 399. 

7.12.2 Prohibited Locations 

Drinking fountains or water coolers shall not be located in public toilet rooms. 

EXCEPTION: Convertible lavatory faucets and fixture fittings that provide a discharge stream similar to a 

drinking fountain shall be permitted in bathrooms in dwelling units. 



2006 National Standard Plumbing Code-Illustrated 



175 



7.13 AUTOMATIC CLOTHES WASHERS 



7.13.1 Compliance 



Automatic clothes washers shall comply with AHAM HLW-2PR or ASSE 1007, and shall have an air gap 
incorporated in the internal tub fill line. 



Comment: Automatic clothes washers that comply with the referenced appliance standards include an 
internal air gap in the water fill line and do not require the installation of an external backftow preven- 
tion device. 



7.14 FOOD-WASTE-GRINDER UNITS 

7.14.1 Compliance 

Domestic food-waste-grinder units shall comply with UL 430 and either AHAM FWD-1 or ASSE 1008. 

7.14.2 Domestic Units 

Domestic food- waste-grinder units shall have not less than a 1-1/2" nominal waste connection to the drainage 
system. Such units may connect to a kitchen sink drain outlet, as permitted under Section 7.1 1 .2.a. 

7.14.3 Commercial Units 

Commercial food-waste-grinder units shall be connected to the drainage system and be separately trapped 
from any sink compartment or other fixture. The waste pipe size for such fixtures shall be of sufficient size to 
serve the fixture but shall be not less than 2-inch nominal size. See Figure 7.14.3 



1 rjfT "■"™^~^^^^^"'" 

2006 National Standard Plumbing Code-Illustrated 



VACUUM BREAKER 




SINK OR INLET CONE 



COMMERCIAL FOOD 
WASTE GRINDER 



2" MINIMUM TRAP 



NOTES: 

1 . The water supply to a commercial food waste grinder must be protected against back-siphonage by 
a vacuum breaker. 

Figure 7.14.3 
A COMMERCIAL FOOD WASTE GRINDER INSTALLATION 

7.14.4 Water Supply 

An adequate supply of water shall be provided for proper operation of food-waste-grinders. 

7.15 DISHWASHING MACHINES 

7.15.1 Compliance 

Domestic dishwashing machines shall comply with UL 749 and either AHAM DW-2PR or ASSE 1006. 
Commercial dishwashing machines shall comply with UL 921 and ASSE 1004. The water supply to 
dishwashing machines shall be protected from back-siphonage by an integral air gap or other internal means. 

7.15.2 Residential Sink and Dishwasher 

The discharge from a residential kitchen sink and dishwasher may discharge through a single 1-1/2" trap. The 
discharge line from the dishwasher shall be not less than the size recommended by the dishwasher manufac- 
turer. It shall either be looped up and securely fastened to the underside of the counter or be connected to a 
deck-mounted dishwasher air gap fitting. The discharge shall then be connected to a branch inlet wye fitting 
between the sink waste outlet and the trap inlet. 
See Figure 7.15.2 



2006 National Standard Plumbing Code-Illustrated 



177 



.— ALTERNATE DECK-MOUNTED 
\ DISHWASHER AIR GAP FITTING 



TO SINK TRAP 



A 



FROM DISHWASHER 



COUNTER TOP- 



iy 2 "c: 




TUBING LOOPED UP HIGH AND FASTENED 
TO UNDERSIDE OF COUNTER 



TRAP - 
TAIL PIECE WITI 
DISHWASHER CONNECTION 



DOMESTIC 
DISHWASHER 



m 



i 



Figure 7.15.2 
A RESIDENTIAL KITCHEN SINK AND DISHWASHER 

7.15.3 Residential Sink, Dishwasher, and Food-Waste-Grinder 

The discharge from a residential kitchen sink, dishwasher, and food-waste-grinder may discharge through a 
single 1-1/2" trap. The discharge line from the dishwasher shall be not less than the size recommended by the 
dishwasher manufacturer. It shall either be looped up and securely fastened to the underside of the counter 
or be connected to a deck-mounted dishwasher air gap fitting. The discharge shall then be connected either 
to the chamber of the food-waste-grinder or to a branch inlet wye fitting between the food-waste-grinder 
outlet and the trap inlet. See Figure 7.15.3 



x— ALTERNATE DECK-MOUNTED 
\ DISHWASHER AIR GAP FITTING 



/ 
TO SINK TRAP 




COUNTER TOP 



HOSE LOOPED UP HIGH AND FASTENED 
TO UNDERSIDE OF COUNTER 



Figure 7.15.3 
A RESIDENTIAL KITCHEN SINK, DISHWASHER, AND FOOD WASTE DISPOSAL 



178 



2006 National Standard Plumbing Code-Illustrated 



7.15.4 Commercial Dishwashing Machine 

a. Commercial dishwashing machines shall be indirectly connected to the drainage system through either 
an air gap or an air break. When the machine is within 5 feet developed length of a trapped and vented floor 
drain, an indirect waste pipe from the dishwasher may be connected to the inlet side of the floor drain trap. 

b. Commercial dishwashers shall be permitted to discharge through a grease interceptor in accordance 
with Section 6.4.2. See Figure 7.15.4 



/"V 




PRE-RINSE SPRAY 



VACUUM BREAKER NOT REQUIRED IF AIR GAP IS MAINTAINED 



V^ 



COMMERCIAL 
DISHWASHER 



3 



ST/ 



ALTERNATE ARRANGEMENT 



7 



AIR GAP OR AIR BREAK 



\—t^ 



VENTED RECEPTOR 



VENTED RECEPTOR 



5 FEET MAX. 
H DEVELOPED 
LENGTH 



Figure 7.15.4 
A COMMERCIAL DISHWASHING MACHINE 



7.16 FLOOR AND TRENCH DRAINS 

7.16.1 Compliance 

Floor and trench drains shall comply with ASME Al 12.6.3 or ASME Al 12.3.1. 

7.16.2 Trap Seal and Strainer 

a. Floor drains shall have a water seal of not less than 2 inches and shall be fitted with a removable 
strainer. The free open area of strainers shall be at least 2/3 of the cross-sectional area of the nominal drain 
outlet size. 

b. Where infrequently used floor drains are subject to evaporation of their trap seals, they shall either 1) be 
provided with a 4-inch trap seal, 2) be fed from an automatic trap priming device, or 3) be arranged as 
otherwise approved by the Authority Having Jurisdiction. 

See Figures 7.16.2-A through-C 



2006 National Standard Plumbing Code-Illustrated 



179 



GRATE MINIMUM AREA 
MUST COMPLY WITH 
A112.21.2M BASED ON 
THE DRAIN OUTLET SIZE 




2"-4" TRAP SEAL 



Figure 7.16.2 - A 
A FLOOR DRAIN TRAP AND STRAINER 



FLOOR DRAIN 



m 



KJX-.i 



t : 'i~'^:''> - 










Wmmm 


i 










f 


A 










4" DEEP SEAL 



Figure 7.16.2 - B 

A DEEP SEAL TRAP 



WATER SUPPLY- 
TO FIXTURE 



^Q 



-— TRAP PRIMING DEVICE WITH 
_, BACKFLOW PROTECTION 
(fixture branch type shown) 



- FLOOR DRAIN EQUIPPED 
WITH PRIMER TRAPPING 



EkJnSgE 



p77 



TRAP SEAL 



NOTES: 

1 . A fixture branch type trap primer can prime more than one trap if it is fitted with a multi-outlet 
manifold. 

Figure 7.16.2 - C 

A FLOOR DRAIN WITH TRAP PRIMER 



180 



2006 National Standard Plumbing Code-Illustrated 



7.16.3 Size of Floor Drains 

a. Floor drains and their branch piping shall be sized on the basis of their normal, expected flow rate. Floor drains 
shall be not less than 2" nominal size. 

b. If provided for emergency showers and eyewash stations, floor drains and their fixture drain branches shall 
be sized for the GPM discharge capacity of the shower or eyewash, but the drainage fixture unit (DFU) loading 
on the sanitary drainage system shall be zero (0.0 DFU). 

7.16.4 Required Locations for Floor Drains 

a. Floor drains shall be installed in the following areas: 

1. Toilet rooms containing either two or more water closets or wall hung urinals or a combination of one or 
more water closets and wall hung urinals, except in a dwelling unit. 

2. Commercial kitchens. 

3 . Common laundry rooms in commercial buildings and buildings having more than two dwelling units. 

7.16.5 Walk-in Coolers and Freezers 

Floor drains located in walk-in coolers and walk-in freezers where food or other products for human con- 
sumption are stored shall be indirectly connected to the drainage system in accordance with Section 9.1.6. 

7.16.6 Floor Slope 

Floors shall be sloped to floor drains where drainage occurs on a regular or frequent basis, or as otherwise 
required by the Authority Having Jurisdiction. 

7.17 GARBAGE CAN WASHERS 

Garbage can washers shall include a removable basket or strainer to prevent large particles of garbage from 
entering the drainage system. The water supply connection shall be protected from back-siphonage in accordance 
with Chapter 10. Garbage can washers shall be trapped and vented as required for floor drains. See Figure 7.17 



BRONZE ADJUSTABLE 
SPRAY NOZZLE 




SEEPAGE OPENINGS 



COLLAR CAN BE USED AS 
FLASHING CLAMP 
(when required) 



STRAINER BUCKET 



WnTn — - — SUPPLY PIPING 



Figure 7.17 
A GARBAGE CAN WASHER 



2006 National Standard Plumbing Code-Illustrated 



181 



7.18 SPECIAL INSTALLATIONS 

7.18.1 Protection of Water Supply 

The water supply to special installations shall be protected from backflow in accordance with Chapter 10. 
Examples of such special installations include decorative fountains, ornamental pools, waterfalls, swimming 
and wading pools, baptisteries, and similar custom-built equipment. 

7.18.2 Approval 

Special installations requiring water supply and/or drainage shall be submitted to the Authority Having Juris- 
diction for approval. 

7.19 FLUSHING DEVICES FOR WATER CLOSETS AND URINALS 

7.19.1 General 

Appropriate flushing devices shall be provided for water closets, urinals, clinical sinks, and other fixtures that 
depend on trap siphonage to discharge the contents of the fixture. 

7.19.2 Separate Devices 

A separate flushing device shall be provided for each fixture. 

EXCEPTION: A single device may be used to automatically flush two or more urinals. 

7.19.3 Flush Tanks: Gravity, Pump Assisted, Vacuum Assisted. 

a. Flush tanks shall have ballcocks or other means to refill the tank after each discharge and to shutoff the 
water supply when the tank reaches the proper operating level. Ballcocks shall be the anti-siphon type and 
comply with ASSE 1002. 

b. Except in approved water closet and flush tank designs, the seat of the tank flush valve shall be at least 
1 inch above the flood level rim of the fixture bowl. 

c. The flush valve shall be designed so that it will close tightly if the tank is flushed when the fixture drain 
is clogged or partly restricted, so that water will not spill continuously over the rim of the bowl or backflow 
from the bowl to the flush tank. 

d. Flush tanks shall include a means of overflow into the fixture served having sufficient capacity to 
prevent the tanks from overflowing with normal flow through the fill valve. 

See Figure 7.19.3 



181 ' 

2006 National Standard Plumbing Code-Illustrated 



VACUUM BREAKER 
(EXTERNALLY LOCATED) 



VACUUM BREAKER 
(INTERNALLY LOCATED) 




REFILL TUBE 
TO OVERFLOW 



FLOAT MECHANISM 



FILL TUBE 



FILL TUBE 



FLUSH VALVE 
ASSEMBLY 




REFILL TUBE 
TO OVERFLOW 



FLOAT MECHANISM 



WATER SUPPLY 



WATER SUPPLY 



Figure 7.19.3 



FLUSH VALVES FOR WATER CLOSET FLUSH TANKS 



7. 1 9.4 Flushometer Tanks (Pressure Assisted) 

Flushometer tanks (pressure assisted) shall comply with ASSE 1037 and shall include built-in pressure regula- 
tion and backflow prevention devices. 

7.19.5 Flushometer Valves 

Flushometer valves shall comply with ASSE 1037 and include a vacuum breaker assembly and means of flow 
adjustment. Flushometer valves shall be accessible for maintenance and repair. 
See Figure 7.19.5 



FLUSHOMETER 
VALVE 




PUSH BUTTON OPERATED 
FLUSHOMETER WITH 
VACUUM BREAKER 



HIGH SECURITY 
WATER CLOSET 



HIGH SECURITY INSTALLATION 



NOTES' TYPICAL INSTALLATION 

1 . Flushometer valves are permitted to be installed in an accessible plumbing chase where security is 
required in detention and correctional institutions. 



Figure 7.19.5 
FLUSHOMETER VALVE INSTALLATIONS 



2006 National Standard Plumbing Code-Illustrated 



183 



7.19.6 Required Water Pressure 

The available water supply pressure shall be adequate for proper operation of the particular flushing devices 

used, as recommended by the manufacturer. 

NOTE: Some one-piece tank-type water closets require 30 psig flowing pressure and 1/2" supplies for proper 

operation. 

7.20 FIXTURES FOR DETENTION AND CORRECTIONAL INSTITUTIONS 

Special design fixtures for use in detention and correctional institutions shall comply with the requirements of this 
Code except that fixtures may be fabricated from welded seamless stainless steel and be equipped with necessary 
security devices. Water closets shall be the elongated type with integral or separate seats. Urinals shall have a 
continuous flushing rim that washes all four walls of the fixture. 

7.21 MINIMUM NUMBER OF REQUIRED FIXTURES 

7.21.1 Number of Fixtures 

Plumbing fixtures shall be provided for the type of building occupancy and in the numbers not less than those 
shown in Tables 7.21.1. 

7.21.2 OccupantLoad 
a. The minimum number of plumbing fixtures sballbebasedonthenumberofpersonstobe servedbythe 

fixtures, as determined by the person responsible for the design of the plumbing system. 

b. Where the occupant load is not established and is based on the egress requirements of a building code, 
the number of occupants for plumbing purposes shall be permitted to be reduced to two-thirds of that for fire 
or life safety purposes. 

c. Wherever both sexes are present in approximately equal numbers, the total occupant load shall be 
multiplied by 50 percent to determine the number of persons of each sex to be provided for, unless specific 
information concerning the percentage of male and female occupants is available. 

d. Plans for plumbing systems, where required, shall indicate the maximum number of persons to be served 
by the facilities. 

e. In occupancies having established seating, such as auditoriums and restaurants, the number of occupants 
for plumbing purposes shall not be less than the number of seats. 

7.21.3 Access to Fixtures 

a. In multi-story buildings, accessibility to the required fixtures shall not exceed one vertical story. 

b. Fixtures accessible only to private offices shall not be counted to determine compliance with this 
section. 

c. The lavatories required by Tables 7.21.1 for employee and public toilet facilities shall be located 
within the same toilet facility as their associated water closets and urinals. 



184 2006 National Standard Plumbing Code-Illustrated 



7.21.4 Separate Facilities 

a. Separate toilet facilities shall be provided for each sex. 
EXCEPTIONS: 

(1). Residential installations. 

(2). In occupancies serving 15 or fewer people, one toilet facility, designed for use by no more than one 
person at a time, shall be permitted for use by both sexes. 

(3) . In business occupancies with a total floor area of 1 500 square feet or less, one toilet facility, de- 
signed for use by no more than one person at a time, shall satisfy the requirements for serving customers 
and employees ofboth sexes. 

(4). In mercantile occupancies with a net occupiable floor area of 1500 square feet or less that is acces- 
sible to customers, one toilet facility designed for use by no more than one person at a time, shall satisfy the 
requirements for serving customers and employees ofboth sexes. 

7.21.5 Substitution and Omission of Fixtures 

a. Urinals: Not more than 50% of the required number of water closets may be substituted with urinals. 

b. Drinking Water Facilities: A kitchen or bar sink shall be considered as meeting the requirements for 
drinking water facilities for employees. 

c. Laundry Trays: Multiple dwelling units or boarding houses without public laundry rooms shall not require 
laundry trays. 

d. Service Sinks: Service sinks may be omitted when the Authority Having Jurisdiction determines that they 
are not necessary for proper cleaning of the facility. 

7.2 1.6 Fixture Requirements for Special Occupancies 

a. Additional fixtures may be required when unusual environmental conditions or special activities are 
encountered. 

b. In food preparation areas of commercial food establishments, fixture requirements may be dictated by 
the health and/or sanitary codes. Fixtures, fixture compartments and appliances used for rinsing or sanitizing 
equipment or utensils, processing or preparing food for sale or serving, shall be installed in accordance with 
Section 9.1.1 to ensure the required protection from backflow and flooding. 

c. Types of occupancy not shown in Tables 7.2 1 . 1 shall be considered individually by the Authority 
Having Jurisdiction. 

d. Where swimming pools operated by an apartment building, condominium, or similar multi-family dwelling 
unit are restricted to the use of residents and guests of residents of dwelling units in the immediate vicinity of the 
pool, the minimum required toilet facilities for bathers within the pool compound shall be one (1) male toilet room 
and one (1) female toilet room, each consisting of a water closet and lavatory as a minimum. 

e. Hand washing facilities shall be provided in each examination room in a doctor's office or medical office. 

7.21.7 Facilities in Mercantile and Business Occupancies Serving Customers 

a. Requirements for customers and employees shall be permitted to be met with a single set of restrooms 
accessible to both groups. The required number of fixtures shall be the greater of the required number for 
employees or the required number for customers. 

b. Fixtures for customer use shall be permitted to be met by providing a centrally located facility acces- 
sible to several stores. The maximum distance of entry from any store to this facility shall not exceed 500 
feet. 

c. In stores with a floor area of 150 square feet or less, the requirement to provide facilities for employees 
shall be permitted to be met by providing a centrally located facility accessible to several stores. The maxi- 
mum distance of entry from any store to this facility shall not exceed 300 feet. 

d. Drinking water facilities are not required for customers where normal occupancy is short term. 



ICC 

2006 National Standard Plumbing Code-llhisiraied 



e. For establishments less than 1500 square feet in total floor area, one water closet and one lavatory in a 
restroom with a lockable door shall be permitted to provide the requirements for serving the customers and 
employees. 

7.21.8 Food Service Establishments 

a. Food service establishments with an occupant load of 101 or more customers shall be provided with 
separate toilet facilities for employees and customers. Customer and employee toilet facilities may be 
combined for customer loads of 100 or less. For employees of 15 or less, one toilet facility, designed for use 
by no more than one person at a time, shall be permitted for use by both sexes. 

b. Drinking water facilities are not required in restaurants or other food service establishments if drinking 
water service is provided. 

7.22 WATER TREATMENT SYSTEMS 

Water softeners, reverse osmosis water treatment units, and other drinking water treatment systems shall 
meet the requirements of the appropriate standards listed in Table 3.1.3. Waste discharge from such equip- 
ment shall enter the drainage system through an air gap. 

7.23 SAFETY FEATURES FOR SPAS AND HOT TUBS 

7.23.1 Spas and Hot Tubs 

Spas and hot tubs shall comply with the requirements of subsections 7.23.2, 7.23.3, and 7.23.4. 

7.23.2 Entrapment Avoidance 

There shall be nothing in the spa or hot tub that can cause the user to become entrapped underwater. Types 
of entrapment can include, but not be limited to, rigid, non-giving protrusions, wedge-shaped openings, and any 
arrangement of components that could pinch and entrap the user. 

7.23.3 Outlets Per Pump 

There shall be a minimum of two (2) suction outlets for each pump in the suction outlet system, separated by 
at least 3 feet or located on two (2) different planes, such as one on the bottom and one on a vertical wall, or 
one on each of two vertical walls. The suction outlets shall be piped so that water is drawn through the 
outlets simultaneously by a common suction line to the pump. Blocking one suction outlet shall not create 
excessive suction at other suction outlets. 

7.23.4 Obstructions and Entrapment Avoidance 

Where vacuum cleaning fittings are provided, they shall be located outside of the spa or hot tub and shall not 
be accessible to the spa or hot tub user. 

7.24 EMERGENCY EQUIPMENT 

Emergency showers and eyewash stations shall comply with ANSI Z358.1 



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2006 National Standard Plumbing Code-Illustrated 



191 



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192 

2006 National Standard Plumbing Code-Illustrated 



■mi 



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Hangers and Supports 



8.1 GENERAL 

a. Hangers and anchors shall be securely attached to the building construction at sufficiently close intervals 
to support the piping and its contents. 

b. Fixtures, appliances and equipment shall be connected to support the weight of the device and any 
additional probable loads that may impact on the device. 

c. Fixtures shall be rigidly supported so that no strain is transmitted in the piping connections. 

8.2 VERTICAL PIPING 

a. Vertical pipe of the following materials shall be supported according to manufacturer's recommendations, 
but no less than the distances listed below: 

1 . Cast-iron soil pipe — at base and at each story height. 

2. Steel threaded pipe — at every other story height. 

3. Copper tube — at each story height but not more than 10-foot intervals. 

4. Lead pipe — four-foot intervals. 

5. Plastic pipe — see Section 8.7. 

6. Flexible plastic tubing — each story height and at mid-story. 

7. Stainless steel drainage pipe — at each story height. 

8.3 HORIZONTAL PIPING 

a. Horizontal pipe of the following materials shall be supported according to manufacturer's recommenda- 
tions, but not less than the distances listed below: 

1 . Cast-iron soil pipe— minimum of one hanger per pipe length located within 1 8 inches of each joint (up to 
10-foot maximum pipe length), at changes in direction, and at branch connections. Where pipe is suspended by 
non-rigid hangers more than 1 8 inches long, provide lateral support at 25-foot maximum spacing. Lateral 
support shall consist of either 1) a sway brace or 2) either a change in direction or a branch connection that 
provides the required lateral support. 

2. Steel threaded pipe— 3/4-inch size and smaller— 10-foot intervals. One-inch size and larger—] 2-foot 
intervals. 

3. Copper tube (1-1/4 inch size and smaller) — 6-foot intervals. 

4. Copper tube (1-1/2 inch size and larger) — 10-foot intervals. 

5. Lead pipe — on continuous metal or wood strips for its entire length. 

6. Plastic pipe — see Section 8.7. 

7. Flexible plastic tubing — 32 inches. 

8. Stainless steel drainage pipe— 10 foot intervals, changes of direction and branch connections. 



2006 National Standard Plumbing Code-Illustrated 



193 



8.4 MATERIAL 

a. Hangers, anchors, and supports shall be of metal or other material of sufficient strength to support the 
piping and its contents. 

b. Piers shall be of concrete, brick, or other masonry construction. 

8.5 STRAIN AND STRESSES IN PIPE 

Piping in the plumbing system shall be installed so as to prevent strains and stresses that will exceed the 
structural strength of the pipe. Provision shall be made for expansion and contraction of the piping. (See 
Sections 4.1.3 and 4.2.16.) See Figures 8.5-A through-C 



PIPE HANGER 
OR SUPPORT 



fl=33=3& 



ANCHOR 




r- GUIDES TO ALLOW FREE 
\ LINEAR MOVEMENT 

pq 



SUFFICIENT 
LENGTH TO 
ALLOW FOR 
EXPANSION 



- GUIDES TO ALLOW FREE 
LINEAR MOVEMENT 



ANCHOR 




PLAN VIEW 

Figure 8.5 - A 
AN EXPANSION LOOP IN A HOT WATER PIPE LINE 



ANCHOR 



GUIDES TO ALLOW FREE -i 
LINEAR MOVEMENT / 



k 




v- GUIDES TO ALLOW FREE 
\ LINEAR MOVEMENT 



ANCHOR 



5 



MECHANICAL EXPANSION JOINT 
(SLIP JOINT TYPE) 



Figure 8.5 - B 
AN EXPANSION COMPENSATOR IN A HOT WATER PIPE LINE 



194 



2006 National Standard Plumbing Code-Illustrated 



GUIDES 



ANCHOR 




v- (JUIUbS —7 

•^^^^^^T I III! lll-TinT iWHBHBBtm 




v- UUIUbS —i 



33 



ANCHOR 



CORRUGATED TUBING 

WITH BRAIDED METAL JACKET 



SUPPORT LOOP (IF HORIZONTAL) 



Figure 8.5 - C 
A FLEXIBLE EXPANSION LOOP TO ABSORB THERMAL EXPANSION 

8.6 BASE OF STACKS 

Bases of cast-iron stacks shall be supported on concrete, brick laid in cement mortar, metal brackets attached 
to the building construction, or by other methods approved by the Authority Having Jurisdiction. Other piping 
material shall be so anchored as to support the stack at the base. 

8.7 SUPPORT OF PLASTIC PIPE 

Hangers and straps shall not compress, distort, cut or abrade the piping and shall allow free movement of the 
pipe. Restraining joints and expansion joints shall be installed as required. Pipe shall be supported at intervals of 
not more than four feet, at end of branches, and at a change of direction or elevation. Supports shall allow free 
movement. Vertical piping shall be maintained in straight alignment. Trap arms in excess of three feet shall be 
supported as close as possible to the trap. Installation shall be in accordance with appropriate standards and 
manufacturer's instructions. 



8.8 UNDERGROUND 

See Section 2.6. 



INSTALLATION 



8.9 SEISMIC SUPPORTS FOR PIPING 

Where earthquake loads are applicable in accordance with the adopted building code, plumbing piping sup- 
ports shall be designed and installed for the seismic forces in accordance with the adopted building code. 



2006 National Standard Plumbing Code-Illustrated 



195 



Blank Page 



1 96 2006 National Standard Plumbing Code-Illustrated 




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Indirect Waste Piping and Special Wastes 



9.1 INDIRECT WASTES 



9.1.1 General 

Drains from fixtures, fixture compartments, equipment, appliances, appurtenances, and other devices 
requiring protection against contamination from backflow or flooding from the drainage system or other 
source shall not be directly connected to any soil, waste, or vent pipe. Such drains shall discharge sepa- 
rately through an air gap or, where permitted, an air break. 

9.1.2 Air Gaps 

The clear air gap between a drain outlet or indirect waste pipe and the flood level rim of an indirect waste 
receptor or other point of disposal shall be not less than twice the diameter of the effective opening of the 
drain served, but not less than one inch. 

9.1.3 Air Breaks 

Where air breaks are permitted, the waste pipe shall be permitted to terminate below the flood level rim 
of the receptor but shall maintain an air space above the top of the receptor's trap seal. Such indirect 
waste pipes shall be permitted to connect to the inlet side of the receptor's trap. 

9.1.4 Where Indirect Wastes Are Required 

Indirect wastes shall be provided for food-handling or food-storage equipment, medical or other sterile 
equipment, clear-water wastes or discharges, and other drains as required herein. 

9.1.5 Food Handling Areas 

a. Fixtures and appliances used for the storage, processing, preparation, serving, dispensing, or sale of 
food shall be drained indirectly. Examples of such fixtures include refrigerated cases, steam kettles, steam 
tables, potato peelers, egg boilers, coffee ums and brewers, culinary sinks used for soaking or washing 
food, ice machines, ice storage bins, drink dispensers, and similar equipment or appliances. A separate 
indirect waste pipe shall be provided for each fixture drain and each shall discharge separately through an 
air gap or air break into a trapped and vented receptor. 

b. Where bar sinks, glass-washing sinks, or other counter sinks cannot be vented according to the 
requirements of Chapter 12, they shall be permitted to each discharge separately to a trapped and vented 
receptor through indirect waste pipes providing either an air break or air gap. See Figures 9.1.5 - A 
through - C 



2006 National Standard Plumbing Code-Illustrated 



197 



CULINARY SINK 



7T 



J 



AIR BREAK OR 
AIR GAP 



/ ~^T ' 'i— RECEPTOR 



(Section 9.3.1) 



CULINARY SINK 



w° 




AIR GAP FITTING 
LOCATE AS CLOSE TO 
THE FIXTURE AS POSSIBLE 



A. MULTIPLE COMPARTMENT SINKS- 

INDIRECT WASTE REQUIRED FOR 
FOOD PREPARATION SINKS 




OUTLET 
AIR GAP FITTING 



X 



- VENTED FLOOR SINK 
I 



B. COMMERCIAL DISHWASHER ARRANGEMENT- AIR BREAK 



AIR GAP IS REQUIRED 
FOR ICE MAKER 



TV 



VENTED FLOOR SINK 
I 



C. ICEMAKING MACHINE 

Figure 9.1.5 - A 
INDIRCT WASTE PIPING IN A FOOD HANDLING AREA 



SODA 
DISPENSER 



1 



X 



BAR SINK 



TZZJ 



VENT — — 



AIR GAP SHOWN 
(CAN BE AIR BREAK) 



FLOOR SINK - 



^X- 



WASTE- 



Figure 9.1.5 - B 
INDIRECT WASTES FOR COUNTER SINKS AND COUNTER-MOUNTED EQUIPMENT 



198 



2006 National Standard Plumbing Code-Illustrated 



FOOD PREP OR 
DISHWASHING 

SINK 



FLOOR DRAIN 




SOIL OR WASTE 
STACK 



NOTES: 

1 . If there is a stoppage in the soil or waste stack, the sewage will overflow from the floor drain 
before it backs up into the food prep or dishwashing sink. 

Figure 9.1.5 - C 

PROTECTING A FOOD PREP OR 

DISHWASHING SINK FROM SEWAGE BACKUP 

EXCEPTIONS: 

(1) Indirect drains shall not be required for domestic kitchen sinks or domestic dishwashers. 

(2) The rinsing and sanitizing compartments of three-compartment commercial sinks shall be drained 
indirectly, in accordance with Section 9. 1 . 1 , but the pot washing compartment shall discharge to the 
drainage system through a grease interceptor in accordance with Section 6.1.1. 

(3) If a properly vented floor drain is installed immediately adjacent to a sink used for dishwashing, a 
properly trapped and vented sink or sink compartment shall be permitted to connect directly to the drain- 
age system, on the sewer side of the floor drain trap. 

9.1.6 Walk-in Coolers and Freezers 

a. If floor drains are located in walk-in coolers or walk-in freezers used for the storage of food or other 
products for human consumption, they shall be indirectly connected to the sanitary drainage system. 

b. Separate indirect waste pipes shall be provided for the floor drains from each cooler or freezer, and 
each shall discharge separately through an air gap or air break into a trapped and vented receptor. 

c. Traps shall be provided in the indirect waste pipe when required under Section 9.2.3. 

d. Indirectly connected floor drains may be located in freezers or other spaces where freezing tempera- 
tures are maintained, provided that traps are not required under Section 9.2.3. Otherwise, the floor of the 
freezer shall be sloped to a floor drain located outside the storage compartment. 

e. The above requirements do not apply to refrigerated food preparation areas or work rooms. 

9.1.7 Medical and Other Sterile Equipment 

Stills, sterilizers, and other sterile equipment requiring drainage shall each discharge separately through an 
air gap into a trapped and vented receptor. 



2006 National Standard Plumbing Code-Illustrated 



199 



9.1.8 Potable Clear-Water Wastes 

Discharges of potable water from the water distribution system, water storage or pressure tanks, water 
heaters, water pumps, water treatment equipment, boilers, relief valves, backflow prevention devices, and 
other potable water sources shall be indirect through an air gap. 

EXCEPTION: An air break shall be permitted where the potable water supply to boilers, water-cooled 
equipment, heating and air-conditioning systems, and similar cross-connections is protected by a backflow 
prevention device in accordance with Section 10.5. 

9.1.9 Drinking Fountains and Water Coolers 

Drinking fountains and water coolers shall be permitted to discharge indirectly through an air break or air 
gap. Where such fixtures are connected to a dedicated drainage stack, the fixtures may connect directly 
to the stack and the stack shall terminate with an air break or air gap. 



9.1.10 Air Conditioning Equipment 

Where condensate or other drainage from air conditioning or cooling equipment discharges to a drainage 
system, it shall discharge indirectly to a trapped and vented receptor through an air break or air gap. 
EXCEPTION: An air break shall not be permitted where the drain connects to a point in the air condition- 
ing equipment that operates at a pressure below atmospheric. 
See Figure 9.1.10 

DIRECTION OF AIR FLOW 



COOLING COIL 




AIR CONDITIONING UNIT 



CONDENSATE PAN (SHOWN UNDER NEGATIVE PRESSURE) 



V-i 



TRAP REQUIRED - 



■ AIR GAP SHOWN - AIR BREAK 
IS ACCEPTABLE IF PRESSURE 
OF CONDENSATE DRAINAGE 
FROM APPLIANCE IS POSITIVE 



t^x 



Figure 9.1.10 
DRAINING AIR CONDITIONING CONDENSATE 



9.1.11 Swimming Pools 

Drainage from swimming pools or wading pools, including pool drains, filter backwash, overflows, and 
pool deck drains, shall discharge indirectly through an air gap to a trapped and vented receptor. 

9.1.12 Relief Valve Discharge Piping 

Discharge piping from relief valves and any associated indirect waste piping shall be in accordance with 
Section 10.16.6. 



200 



2006 National Standard Plumbing Code-Illustrated 



9.2 INDIRECT WASTE PIPING 

9.2.1 Materials and Installation 

Indirect waste piping shall be of materials approved for sanitary drainage under Section 3.5. 

9.2.2 Pipe Size 

Indirect waste piping shall be not less than the nominal size of the drain outlet on the fixture or equipment 
served. 

9.2.3 Fixture Traps 

Traps shall be provided at fixtures and equipment connections where the developed length of indirect 

waste piping exceeds ten feet. 

EXCEPTION: Drain lines used for clear-water wastes. 

9.2.4 Provisions for Cleaning 

Indirect waste piping shall be installed in a manner to permit ready access for flushing and cleaning. 
Where necessary, cleanouts shall be provided in accordance with Section 5.4. 

9.3 INDIRECT WASTE RECEPTORS 

9.3.1 General 

a. Receptors for indirect wastes shall be properly trapped and vented floor drains, floor sinks, 
standpipes, open-hub drains, air gap fittings, or other approved fixtures. 

b. Receptors shall be of such size, shape, and capacity as required to prevent splashing or flooding by 
the discharge from any and all indirect waste pipes served by the receptor. 

c. Plumbing fixtures that are used for domestic or culinary purposes shall not be used as receptors for 
indirect wastes, except as follows: 

EXCEPTIONS: 

(1 ) In a dwelling unit, a kitchen sink trap, or food waste grinder, shall be permitted to receive the 
discharge from a dishwasher. 

(2) In a dwelling unit, a laundry sink, provided that an air gap is maintained for any potable clear-water 
waste, shall be an acceptable receptor for: 

a. Air conditioning condensate. 

b. Automatic clothes washer. 

c. Water treatment unit. 

d. Water heater relief valve discharge. 

(3) A service sink or mop basin shall be an acceptable receptor for air conditioning condensate and 
any infrequent potable clear-water waste if the required air gap is provided for potable clear- water 
wastes. 

See Figures 7.15.2, 7.15.3, 7.15.4, 9.1.5-A, 9.1.5-B, and 9.1.10 

9.3.2 Strainers or Baskets 

Floor sinks and floor drains that handle other than clear-water wastes shall include an internal or a readily 
removable metal basket to retain solids. See Figure 9.3.2 



2006 National Standard Plumbing Code-Illustrated 201 




ooooooooo 
ooooooooo 

OOOOOOOOO] 

oooooooo 
oooooooo 




OPTIONAL FLAT BOTTOM STRAINER 



RECEPTOR 

WITH 

DOMED BOTTOM 

STRAINER 



RECEPTOR 

WITH 

REMOVABLE 

BASKET 



NOTES: 

1 . Receptors may have a partially open top grate. 

2. Domed bottom strainers help to reduce splashing. 

3. In the receptor with a basket, the optional flat bottom strainer protects the drain line while the 
basket is removed. 

Figure 9.3.2 
FLOOR SINKS WITH STRAINER OR BASKET 



9.3.3 Prohibited Locations 

Receptors for indirect wastes shall not be located in a toilet room or in any confined, concealed, inacces- 
sible, or unventilated space. 

EXCEPTION: Air conditioning condensate in dwellings shall be permitted to drain to a tub waste and 
overflow or lavatory tailpiece in accordance with Section 9.4.3.C.5. 

9.3.4 Standpipes 

A standpipe, 2-inch minimum pipe size and extending not more than 48 inches nor less than 18 inches 
above its trap, shall be permitted to serve as a receptor for a domestic clothes washer. In a dwelling, a 
laundry sink shall be permitted to drain into the standpipe. See Figure 9.3.4 



202 



2006 National Standard Plumbing Code-Illustrated 



Di" or iy 2 " 

VENT 



2" MIN. DRAIN 




BETWEEN 18" AND 48" 



2" MIN. TRAP 




STANDPIPE FOR 
DOMESTIC CLOTHES WASHER 



STANDPIPE FOR 
FLOOR DRAIN 




VENT 



LAUNDRY TRAY AND 

CLOTHES WASHER DRAIN 

(SINGLE FAMILY DWELLINGS ONLY) 



NOTES: 

1 . Standpipes shorter than 1 8" may cause splashing and overflow. 

2. Standpipes taller than 48" may cause the trap to self-siphon. They may also retain waste 
particles and create an odor problem. 

Figure 9.3.4 
STANDPIPE RECEPTORS 



9.3.5 Open-hub Drains 

A trapped and vented open-end drain pipe extending not less than 2 inches above the surrounding floor 
shall be permitted to serve as a receptor for clear-water wastes. 

9.3.6 Minimum Receptor Pipe Size 

a. The minimum drain pipe size for an indirect waste receptor shall be at least one pipe size larger than 
the indirect waste pipe that it serves. 

EXCEPTION: A laundry sink receiving the discharge from an automatic clothes washer under Section 
9.3.1.b.2. 

b. Where a receptor receives indirect drainage from two or more fixtures, the cross-sectional area of the 
receptor drain shall be not less than the aggregate cross-sectional area of all indirect waste pipes served 
by the receptor. For the purposes of this requirement, 1-1/4" pipe = 1.2 in 2 , 1-1/2" pipe = 1.8 in 2 , 2" pipe 
= 3.1 in 2 , 2-1/2" pipe = 4.9 in 2 , 3" pipe = 7.1 in 2 , 4" pipe = 12.6 in 2 , 5" pipe = 19.6 in 2 , and 6" pipe = 
28.3 in 2 . See Figure 9.3.6 



2006 National Standard Plumbing Code-Illustrated 



203 



1 1„ 



□ 



11" 
2 

on 



1.1" 
2 

on 




NOTES: 

1 . The aggregate cross-sectional area of three 1-1/2" indirect waste pipes is 3 x 1 .8 = 5.4 square 
inches. A 2" outlet size is only 3.1 square inches. The minimum receptor outlet pipe size is 3" 
with 7.1 square inches. 

Figure 9.3.6 
MINIMUM RECEPTOR OUTLET PIPE SIZE 



9.3.7 Drainage Fixture Unit (DFU) Values 

The drainage fixture unit values used to combine the loading of indirect waste receptors with other 
fixtures shall be the sum of the DFU values for all fixtures that are indirectly drained into the receptor. 

9.4 SPECIAL WASTES 

9.4.1 Treatment of Corrosive Wastes 

Corrosive liquids, spent acids, or other harmful chemicals that may damage a drain, sewer, soil or waste 
pipe, create noxious or toxic fumes, or interfere with sewage treatment processes shall not be discharged 
into the plumbing system without being thoroughly neutralized or treated by passing through a properly 
constructed and approved neutralizing device. Such devices shall be provided automatically with a suffi- 
cient supply of neutralizing medium, so as to make its contents non-injurious before discharge into the 
drainage system. The nature of the corrosive or harmful waste and proposed method of its treatment shall 
be submitted to and approved by the Authority Having Jurisdiction prior to installation. See Figures 
9.4.1 and 1.2.55 



204 



2006 National Standard Plumbing Cade-Illustrated 



-SENSOR WIRE 

-SOLENOID VALVE 



VACUUM BREAKER (APPROVED TYPE) 
ASPIRATOR 



NEUTRALIZING 
SOLUTION 




-POTABLE WATER 



HARMFUL 
CHEMICALS 



— OUTLET FLOW 



TREATMENT 
TANK 



NOTES: 

1 . The automatic system can neutralize acids or caustic, depending on what neutralizing solution 

is used. If the system had two chemical feeders, it could neutralize both acid and caustic 

wastes. 

Figure 9.4.1 
AN AUTOMATIC WASTE TREATMENT NEUTRALIZING TANK 



9.4.2 High Temperature Wastes 

No waste at temperatures above 140°F shall be discharged directly into any part of a drainage system. 
Such wastes shall be discharged to an indirect waste receptor and a means of cooling shall be provided 
where necessary. 

9.4.3 Air Conditioning Condensate 

a. Indirect waste piping from air conditioning units shall be sized according to the condensate-generating 
capacity of the units served. Branches from individual units shall be no smaller than the drain opening or 
drain connection on the unit. Traps shall be provided at each air conditioning unit or cooling coil to main- 
tain atmospheric pressure in the waste piping. 

b. Condensate waste piping shall be sloped not less than 1/8" per foot. Drainage fittings shall be used in 
sizes 1-1/4" and larger. Minimum pipe sizing shall be as follows: 

3/4" pipe size through 3-ton cooling capacity 
1 " pipe size through 20-ton cooling capacity 



2006 National Standard Plumbing Code-Illustrated 



205 



1-1/4" pipe size through 1 00-ton cooling capacity 

1-1/2" pipe size through 300-ton cooling capacity 

2" size pipe through 600-ton cooling capacity 
c. Discharge of air conditioning condensate shall not be permitted to create a nuisance such as by flowing 
across the ground or paved surfaces. Unless expressly prohibited by the Authority Having Jurisdiction, 
the point of indirect discharge for air conditioning condensate shall be one of the following: 

1 . The building sanitary drainage system. 

2. The building storm drainage system. 

3. A sump pump. 

4. A subsurface absorption pit or trench. 

5. Within dwellings, a tub waste and overflow or lavatory tailpiece within the same dwelling. 
See Figure 9.4.3-A and-B 





3 
TONS 




l °'* 




3 TONS = 3/4" MIN. c 


f" MIN. \> 



6TONS = 1"MIN.- 



9TONS = 1"MIN- 



3/4" 



3 
TONS 



MIN. 



3/4' 



MIN 



■r*r 



3 
TONS 



TO POINT 
OF DISPOSAL 



NOTES: 

1 . The condensate drain traps on air conditioning (cooling) units must have sufficient trap seal 
depth to offset the static pressure {positive or negative) at the condensate drain connection of 
the unit. The traps are shown with a seal depth for a negative pressure 

Figure 9.4.3 - A 
SIZING INDIRECT WASTE PIPING FOR AIR CONDITIONING CONDENSATE 



206 



2006 National Standard Plumbing Code— Illustrated 



AIR 

CONDITIONING 

UNIT 



321 



V 



TO POINT 

OF DISCHARGE 



TO A RECEPTOR 



TO POINT OF , 

DISCHARGE T "TV 



AIR 

CONDITIONING 
UNIT 



fbi 



D 







- FULL PORT 
SHUTOFF VALVE 

• CHECK VALVE 



LJ 



TO A SUMP PUMP 




THERMOSTAT 

ACCESSIBLE 

-TO OCCUPANT 



LAVATORY 



BRANCH 
TAILPIECE 





BRANCH WYE FITTING 



EXAMPLES OF LAVATORY OR 

BATHTUB CONDENSATE 

CONNECTIONS 



CONDENSATE 
PIPING 



OVERFLOW TAPPED 
TO RECIEVE 
CONDENSATE PIPING 



Figure 9.4.3 - B 
DISCHARGING AIR CONDITIONING CONDENSATE 



2006 National Standard Plumbing Code-Illustrated 



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Blank Page 



208 2006 National Standard Plumbing Code-Illustrated 



Chapter 10 



Water Supply and Distribution 



10.1 QUALITY OF WATER SUPPLY 

Only potable water shall be supplied to plumbing fixtures used for drinking, bathing, culinary use or the processing 
of food, medical or pharmaceutical products. 

10.2 IDENTIFICATION OF POTABLE AND NON-POTABLE WATER 

In buildings where dual water distribution systems are installed, one potable water and the other non-potable water, 
each system shall be identified either by color marking or metal tags, or other appropriate methods such as may be 
approved by the Authority Having Jurisdiction. Each outlet on the non-potable water line that may be used for 
drinking or domestic purposes shall be posted: DANGER-UNSAFE WATER. See Figure 10.2 



SERVICE AND BACKGROUND COLOR 

Potable Water = GREEN 
Non-Potable Water = YELLOW 
Cold Water Supply = GREEN 
Hot Water Supply - YELLOW 
Hot Water Return = YELLOW 
Sanitary Drain = GREEN 
Plumbing Vent = GREEN 
Waste = GREEN 
Waste (corrosive) - YELLOW 
Storm Drain = GREEN 
Roof Drain = GREEN 
Fire Protection = RED 



NOTES: 

1 . Color coding of piping is based on ANSI A13.1 - Scheme for the Identification of Piping Systems. 

Figure 10.2 
COLOR CODING FOR PIPING 



2006 National Standard Plumbing Code-Illustrated 



209 



10.3 WATER REQUIRED 

10.3.1 Buildings 

Plumbing fixtures shall be provided with a potable supply of water in the amounts and at the pressures 
specified in this Chapter. 

10.4 PROTECTION OF POTABLE WATER SUPPLY 

10.4.1 General 

A potable water supply shall be designed, installed and maintained to prevent contamination from non-potable 
liquids, solids or gases by cross connections. 

10.4.2 Interconnections 

Interconnections between two or more public water supplies shall be permitted only with the approval of the 
Authority Having Jurisdiction. 

10.4.3 Cross Connection Control 

Potable water supplies shall be protected in accordance with the cross connection control program of the 
Authority Having Jurisdiction and the provisions of this Code. Cross connection control shall be provided at 
individual outlets, and where required, by containment of the premises. Each potential cross connection within 
the premises shall be protected. Where containment is required, the potable water supply shall be protected 
by a backflow protection device installed immediately downstream of the meter or between the service 
shutoff valve and the first outlet or branch connection. See Figures 10.4.3 - A and - B 



^\ 



% 



VACUUM 
BREAKER 






B 



,f 



AIR GAP 



H 



■& 




FAUCET 
VACUUM BREAKER 



RUBBER HOSE 
MOP SINK 
r FINISHED FLOOR 



URINAL 



BATHTUB 



MOP SINK 



NOTES: 

1 . Individual outlet protection is required by this Code. It protects the potable water distribution 
piping from being contaminated by a cross connection within the property. 

Figure 10.4.3 - A 
CROSS CONNECTION CONTROL BY INDIVIDUAL OUTLET PROTECTION 



210 



2006 National Standard Plumbing Code-Illustrated 



BACKFLOW PREVENTION DEVICE 
TO CONTAIN BACKFLOWS TO 
WITHIN THE PROPERTY 



PUBLIC WATER' 
MAIN 




BUILDING WATER SERVICE 



BUILDING SERVICE 
SHUTOFF VALVE — 



NOTES: 

1 . Cross connection control by containment protects the public water supply from being contaminated 
by a cross connection within a customer's property. 

Figure 10.4.3 - B 
CROSS CONNECTION CONTROL BY CONTAINMENT OF THE BUILDING 



10.4.4 Private Supplies 

a. Private potable water supplies (i.e., wells, cisterns, lakes, streams) shall require the same backflow 
protection that is required for a public potable water supply. 

b. Cross connection between a private potable water supply and a public potable water supply shall not be 
made unless specifically approved by the Authority Having Jurisdiction. 



Comment: Interconnections between private water supplies and public water supplies are generally 
prohibited because private supplies are usually not monitored continuously for water quality. 



10.4.5 Toxic Materials 

a. Piping conveying potable water shall be constructed of non-toxic material. 

b. The interior surface of a potable water tank shall not be lined, painted, or repaired with any material that 
will affect either the taste, odor, color or potability of the water supply when the tank is placed in or returned 



to service. 



Comment: The toxicity rating of a piping material can be found in the material standard listed in Table 
3.1.3. The piping materials listed in Table 3.4 are non-toxic and are suitable for conveying potable 
water. 



10.4.6 Reserved 

10.4.7 Reserved 

10.4.8 Used Materials 

Materials that have been used for any purpose other than conveying potable water shall not be used for 
conveying potable water. 



2006 National Standard Plumbing Code-Illustrated 



211 



10.4.9 Water As a Heat-Transfer Fluid 

Potable water may be used as a heat-transfer fluid provided the system design is approved by the Authority 
Having Jurisdiction. 

10.5 BACKFLOW PREVENTION 

10.5.1 Plumbing Fixtures, Appliances, Water Supply Outlets 

The water supply shall be protected from back-siphonage by a fixed air gap between the potable water outlet 
and the overflow level of the fixture or receptor. 

10.5.2 Requirements for Air Gaps 

a. How Measured: The air gap shall be measured vertically from the lowest end of a potable water outlet 
to the flood rim or line of the fixture or receptor into which it discharges. 

b. Minimum Size (distance): The minimum required air gap shall be twice the effective opening of a potable 
water outlet unless the outlet is a distance less than 3 times the effective opening away from a wall or similar 
vertical surface in which case the minimum required air gap shall be 3 times the effective opening of the 
outlet. In no case shall the minimum required air gap be less than that shown in Table 10.5.2. See Figure 
10.5.2 

Table 10.5.2 
MINIMUM AIR GAPS FOR PLUMBING FIXTURES 



Minimum Air Gap 



Fixture 



When not Affected 

By Near Wall 1 

(Inches) 



Effective openings greater than one inch 



When Affected 

By Near Wall 2 

(Inches) 



Lavatories with effective opening not 
greater than 1/2 inch diameter 


1 


1-1/2 


Sink, laundry trays, goose-neck bath faucets and other fixtures 
with effective openings not greater than 3/4" diameter 


1-1/2 


2-1/4 


Over rim bath fillers and other fixtures with 
effective openings not greater than 1 inch diameter 


2 


3 


Drinking water fountains-single orifice not greater than 7/16 
(0.437) in. diameter or multiple orifices having total area of 
0.1 50 square inches (area of circle 7/16 in. diameter) 


1 


1-1/2 



2X 3X 

diameter of diameter of 

effective opening effective opening 



1 . Side walls, ribs or similar obstructions do not affect air gaps when spaced from inside edge of the spout opening a distance greater than 
three times the diameter of the effective opening for a single wall, or a distance greater than four times the diameter of the effective opening for 
two intersecting walls. 

2. Vertical walls, ribs, or similar obstructions extending from the water surface to or above the horizontal plane of the spout opening require 
a greater air gap when spaced closer to the nearest inside edge of the spout opening than specified in Note 1 . above. The effect of three or more 
such vertical walls or ribs has not been determined. In such cases, the air gap shall be measured from the top of the wall. 



212 



2006 National Standard Plumbing Code-Illustrated 



r 



AIR GAP - 2 TIMES THE DIAMETER "D" 
BUT NOT LESS THAN V 




TYPICAL LAVATORY FAUCET - AIR GAP 



tA- 



A1R GAP - 
2 TIMES THE 
DIAMETER "D' 
BUT NOT 
LESS THAN 2" 



_! £_/ — I, 

d-HH- 



=F 



TYPICAL TUB FILLER - AIR GAP 

NOTES: 

1 . Diameter "d" is the opening on the faucet aerator, tub spout, or outlet pipe 



Figure 10.5.2 
MINIMUM REQUIRED AIR GAPS 

10.5.3 Required Backflow Prevention Devices 

The following requirements shall apply: 

A. Backsiphonage, Non-Continuous Pressure, Non-Health Hazard 

1. Atmospheric vacuum breaker - ASSE 1001 (AVB) 

2. Hose connection vacuum breaker - ASSE 1011 

3. Any backflow protection device approved for protection against backsiphonage with non- 
continuous or continuous pressure and a non-health hazard or health hazard. 

B. Backsiphonage, Continuous Pressure, Non-Health Hazard 

1. Pressure vacuum breaker - ASSE 1020 (PVB) 

2. Spill-resistant vacuum breaker - ASSE 1056 (SVB) 

3. Backflow preventer with intermediate atmospheric port - ASSE 1012 

4. Double check valve assembly ASSE 1015 (DC and DCVA) 

5. Any backflow protection device approved for protection against backsiphonage with continu- 
ous pressure and a non-health hazard or health hazard. 

C. Backsiphonage, Non-Continuous Pressure, Health Hazard 

1. Atmospheric vacuum breaker - ASSE 1001 (AVB) 

2. Hose connection backflow preventer - ASSE 1052 

3. Any backflow protection device approved for protection against backsiphonage with non- 
continuous or continuous pressure and a health hazard. 



2006 National Standard Plumbing Code-Illustrated 



213 



D. Backsiphonage, Continuous Pressure, Health Hazard 

1. Pressure vacuum breaker - ASSE 1020 (PVB) 

2. Spill-resistant vacuum breaker - ASSE 1056 (SVB) 

3. Reduced pressure backflow preventer assembly - ASSE 1013 (RP, RPZ, and RPBA) 

4. Any backflow protection device approved for protection against backsiphonage with continuous 
pressure and a health hazard. 

E. Back Pressure, Non-Health Hazard 

1. Dual check backflow preventer - ASSE -1024 (DuCh) 

2. Double check valve assembly - ASSE 1015 (DC)(DCVA) 

3. Reduced pressure backflow preventer assembly - ASSE 1013 (RP)(RPZ)(RPBA) 

F. Back Pressure, Health Hazard 

1. Reduced pressure backflow preventer assembly - ASSE 1013 (RP)(RPZ)(RPBA) 

10.5.4 Approval of Devices 

Backflow prevention devices shall be listed or certified by a recognized certification body as complying with 
the appropriate standards in Table 3.1.3 - Part IX. 

10.5.5 Installation of Backflow Preventers 

a. Devices of All Types: All backflow prevention devices shall be accessible. Backflow prevention devices 
having atmospheric vents shall not be installed in pits, vaults, or similar potentially submerged locations. 
Vacuum breakers and other devices with vents to atmosphere shall not be located within fume hoods. 

b. Atmospheric Vacuum Breakers: Pipe applied atmospheric vacuum breakers shall be installed with the 
critical level at least six inches above the flood level rim or highest point of discharge of the fixture being 
served. Approved deck-mounted and pipe-applied vacuum breakers and vacuum breakers within equipment, 
machinery and fixtures where the critical level is a specified distance above the source of contanination shall 
be installed in accordance with manufacturer's instructions with the critical level not less than one inch above 
the flood level rim. Such devices shall be installed on the discharge side of the last control valve to the fixture 
and no shut-off valve or faucet shall be installed downstream of the vacuum breaker. Vacuum breakers on 
urinals shall be installed with the critical level six inches above the flood level rim. 

See Figures 10.5.5 - A through - F. Also Figures 10.5.10 - A through - C 

c. Pressure Type Vacuum Breakers: Pressure type vacuum breakers shall be installed with the critical level 
at a height of at least 12 inches above the flood level rim for ASSE 1020 devices and with the critical level at 
least six inches above the flood level rim or highest point of discharge of the fixture being served for ASSE 
1056 devices. Deck-mounted and pipe-applied pressure type (ASSE 1056) vacuum breakers within equip- 
ment, machinery and fixtures where the critical level is a specified distance above the source of contamina- 
tion shall be installed in accordance with manufacturer's instructions with the critical level not less than one 
inch above the flood level rim. See Figure 10.5.5 - G. Also Figures 10.5.10 - D and - E 

d. Double Check Valves and Reduced Pressure Principle Valves: Such devices shall be installed at not less 
than 1 2 inches above the floor or permanent platform with the maximum of 60 inches above floor or perma- 
nent platform. See Figures 10.5.5 - H and - I. Also 10.5.10 - F 

e. Spill-resistane Vacuum Breakers: Approved deck mounted and pipe-applied spill-resistant vacuum 
breakers within equipment, machinery and fixtures where the critical level is a specified distance above the 
source of contamination shall be installed in accordance with manufacturer's instructions with the critical level 
not less than one inch above the flood level rim. 



214 



2006 National Standard Plumbing Code-Illustrated 



ATMOSPHERIC VACUUM BREAKER 
ACCESSIBLE 



6" MINIMUM FROM C-L 
TO FLOOD RIM LEVEL 




ON-OFF SWITCH 



NOTES: 

1 . If the critical level (C-L) is not marked on the vacuum breaker body, the bottom of the valve is 
considered to be the C-L reference. 

2. Atmospheric vacuum breakers are not rated for periods of more than 1 2 hours of continuous water 
pressure. 

Figure 10.5.5 - A 

THE POTABLE WATER SUPPLY TO A COMMERCIAL FOOD WASTE GRINDER 

PROTECTED BY AN ATMOSPHERIC VACUUM BREAKER 



ATMOSPHERIC 
VACUUM BREAKER 



POTENTIALLY SUBMERGED HOSE 




NOTES: 

1 . Atmospheric vacuum breakers are not rated for periods of more than 1 2 hours of continuous water 
pressure. 

Figure 10.5.5 - B 
THE POTABLE WATER SUPPLY TO A SERVICE SINK 
PROTECTED BY AN ATMOSPHERIC VACUUM BREA 



2006 National Standard Plumbing Code-Illustrated 



215 



ATMOSPHERIC 
VACUUM BREAKER 



POTENTIALLY SUBMERGED HOSE 




NOTES: 

1 . Atmospheric vacuum breakers are not rated for periods of more than 1 2 hours under continuous 
water pressure. 

Figure 10.5.5 - C 

THE POTABLE WATER SUPPLY TO A LAB SINK 

PROTECTED BY AN ATMOSPHERIC VACUUM BREAKER 



6" MIN. 
CRITICAL LEVEL 



SHUTOFF 
VALVE 



ATMOSPHERIC VACUUM BREAKER 



ASPIRATOR 




VACUUM HOSE 



SUCTION DEVICE 



NOTES: 

1 . Atmospheric vacuum breakers are not rated for periods of more than 1 2 hours under continuous 
water pressure. 

Figure 10.5.5 - D 

THE POTABLE WATER SUPPLY TO AN ASPIRATING DEVICE 

PROTECTED BY AN ATMOSPHERIC VACUUM BREAKER 



216 



2006 National Standard Plumbing Code-Illustrated 



FLUSHOMETER 
VALVE 




ATMOSPHERIC 
VACUUM BREAKER 

CRITICAL LEVEL MARKING 



NOTES: 

1 Atmospheric vacuum breakers are not rated for periods of more than 1 2 hours under continuous 
water pressure. 

Figure 10.5.5 - E 

THE POTABLE WATER SUPPLY TO A WATER CLOSET OR URINAL 

PROTECTED BY AN ATMOSPHERIC VACUUM BREAKER 



CRITICAL LEVEL 
1" ABOVE 
OVERFLOW 



1 



r 



.c 




ANTI-SIPHON BALLCOCK WITH 
INTERGRAL VACUUM BREAKER 



WATER SUPPLY — 



^FILL TUBE 



■REFILL TUBE j 

■OVERFLOW TUBE 




■ FLAPPER 



■ FLUSH VALVE 



FLUSH VALVE ASSEMBLY 



Figure 10.5.5 - F 

THE POTABLE WATER SUPPLY TO A WATER CLOSET GRAVITY FLUSH TANK 

PROTECTED BY AN ANTI-SIPHON BALLCOCK WITH INTEGRAL VACUUM BREAKER 



2006 National Standard Plumbing Code-Illustrated 



217 



ASSE 1020 ANTI-SIPHON 
PRESSURE VACUUM BREAKER 



■SEE NOTES 1&4 



SEE NOTE 3 



TO OTHER FIXTURES 
REQUIRING POTABLE WATER 




4/~" — - POTABLE WATER SUPPLY 



NOTES: 

1. ASSE 1020 anti-siphon pressure vacuum breakers can be located where subjected to continuous pressure. 

2. The critical level (C-L) of the vacuum breaker must be at least 12" higher than the highest downstream piping. 

3. Shutoff valves are permitted downstream from pressure vacuum breakers. 

4. ASSE 1020 pressure vacuum breakers should not be located where water spillage from the atmospheric 

vent will cause damage or create a nuisance. If necessary, use ASSE 1056 spill-resistant vacuum breakers. 

Figure 10.5.5 - G 

THE POTABLE WATER SUPPLY TO INDUSTRIAL PROCESS EQUIPMENT 

PROTECTED BY AN ANTI-SIPHON PRESSURE VACUUM BREAKER 




— /- 



TO NON HEALTH HAZARD-BACKPRESSURE 
BACKFLOW APPLICATIONS 



TEST PORTS 



See Note 2 



- FLOOR OR WORKING SURFACE 



NOTES: 

1. Double check valve assemblies or reduced pressure backflow preventor assemblies are required for back 
pressure applications. 

2. Double check valve assemblies must be installed between 12" and 60" above the floor or other working 
surface to provide sufficient access for periodic testing and maintenance. 

3. Double check valve assemblies subject to back-siphonage require an intermediate vacuum breaker and a 
relief vent. 

4. Double check valve assemblies with an intermediate vacuum breaker and relief vent must not be located in 
pit or other area subject to flooding. The relief vent will create a cross-connection if submerged. 

Figure 10.5.5 - H 

THE POTABLE WATER SUPPLY TO A NON-HEALTH HAZARD BACKFLOW APPLICATION 

PROTECTED BY A DOUBLE CHECK VALVE ASSEMBLY 



218 



2006 National Standard Plumbing Code-Illustrated 



TO A BACK-PRESSURE HEALTH HAZARD BACKFLOW APPLICATION SUCH AS 
COOLING TOWER MAKEUP, BOILER WATER MAKEUP, OR HYDRONIC PIPING 
SYSTEM MAKEUP WHERE CHEMICAL TREATMENT IS PROVIDED AND THE 
WATER IN THE PIPING SYSTEM IS NOT POTABLE. 



REDUCED PRESSURE ZONE 
BACKFLOW PREVENTOR ASSEMBLY 



TEST PORTS 




3 



- RESILIENT SEATED 
SHUTOFF VALVES 



See Note 2 



AIR GAP OR 
AIR GAP FITTING 

LJ 



• FLOOR OR WORKING SURFACE 



NOTES: 

1. Double check valve assemblies are not permitted for health hazard applications. 

2. Reduced pressure zone principle backflow prevention devices must be installed between 12" and 
60" above the floor or other working surface to provide sufficient access for periodic testing and 
maintenance. 

3. RPZ devices must not be installed in pits or other area subject to flooding. The relief vent will create 
a cross-connection if submerged. 

4. If occasional spillage from the relief vent will cause damage or be a nuisance, the vent must be 
equipped with an air gap fitting and indirectly drained to an acceptable point of disposal. 



Figure 10.5.5 - I 

THE POTABLE WATER SUPPLY TO A HEALTH HAZARD BACKFLOW APPLICATION 

PROTECTED BY A REDUCED PRESSURE BACKFLOW PREVENTER ASSEMBLY 



10.5.6 Maintenance and Testing of Backflow Prevention Devices 

a. Devices installed in a building potable water supply distribution system for protection against 
backflow shall be maintained in good working condition by the person or persons responsible for the 
maintenance of the system. 

b. Devices that are designed to be field tested shall be tested prior to final inspection of the initial installa- 
tion and once each year thereafter, using field test procedures conforming to ASSE 5010 Series Professional 
Qualifications Standards or equivalent. 



2006 National Standard Plumbing Code-Illustrated 



219 



NOTE: Testable devices are those backflow prevention devices having test cocks and include, but are not 
limited, to the following: 

1. Pressure vacuum breakers 

2. Spill-resistant vacuum breakers 

3. Double check valve assemblies 

4. Double check detector assemblies 

5. Reduced pressure backflow preventer assemblies 

6. Reduced pressure detector assemblies 

c. Where tests indicate that the device is not functioning properly, it shall be serviced or repaired in 
accordance with the manufacturer's instructions and be retested. 

d. Testing and repair of devices shall be performed by certified individuals approved by an agency 
acceptable to the Authority Having Jurisdiction. Certification for testing shall be in accordance with ASSE 
5000 or equivalent. Certification for repair shall be in accordance with ASSE 5030 or equivalent. Certification 
shall include not less than 32 hours of combined classroom and practice training and successful completion of 
a written and practical examination. 

e. Copies of test reports for the initial installation shall be sent to the Authority Having Jurisdiction and the 
water supplier. Copies of annual test reports shall be sent to the water supplier. 

f. Where a continuous water supply is critical and cannot be interrupted for the periodic testing of a 
backflow prevention device, multiple backflow prevention devices or other means of maintaining a continuous 
supply shall be provided that does not create a potential cross connection. 

10.5.7 Tanks and Vats — Below Rim Supply 

a. Where a potable water outlet terminates below the rim of a tank or vat and the tank, or vat has an 
overflow of a diameter not less than given in Table 10.8.3, the overflow pipe shall be provided with an air gap 
as close to the tank as possible. 

b. The potable water outlet to the tank or vat shall terminate a distance not less than 1-1/2 times the height 
to which water can rise in the tank above the top of the overflow. This level shall be established at the 
maximum flow rate of the supply to the tank or vat and with all outlets closed except the air-gapped overflow 
outlet. 

c. The distance from the outlet to the high water level shall be measured from the critical point of the 
potable water supply outlet. 

See Figure 10.5.7. Also Sections 10.8.3, 10.8.4, 10.8.5, and 10.8.6 



220 



2006 National Standard Plumbing Code-Illustrated 



TANK WATER LEVEL 
CONTROL VALVE 



MAKE-UP 

WATER SUPPLY 




REQUIRED AIR GAP 
(See Note 5) 

MAXIMUM OVERFLOW 
WATER LEVEL 
(See Note 4) 



-REQUIRED COVER 



TANK OVERFLOW- 
See Note 2 



fe 



-TANK VENT 
See Note 1 



INVERT OF OVERFLOW PIPE 



POTABLE WATER 



TANK OUTLET - 



-TANK DRAIN VALVE 




POTABLE WATER TO 
BOOSTER PUMP OR 
GRAVITY SUPPLY TO 
WATER DISTRIBUTION 
SYSTEM 



NOTES: 



1. 



3. 
4. 



The covers of potable water tanks or vats must have screened vent pipes with internal areas not less 

than that of the outlet pipe. 

The size of the overflow pipe must comply with Table 10.8.3, based on the maximum makeup water 

flow rate. 

The air gap at the tank overflow discharge must be 2 X the inside diameter of the overflow pipe. 

The maximum overflow water level must be established based on the size of the overflow pipe and 

the maximum available makeup water flow. Calculated required static head or rise above the invert 

of the overflow should be confirmed by operational tests under actual full flow conditions with the 

tank outlet(s) closed. 

The required air gap at the water inlet to the tank or vat must be at least 1-1/2 times the rise in 

water level above the invert of the overflow outlet under maximum overflow conditions, measured from 

the invert of the tank overflow. 



Figure 10.5.7 
A POTABLE WATER TANK OR VAT WITH ITS INLET BELOW THE OVERFLOW RIM 

10.5.8 Connections to Carbonated Beverage Dispensers 

The water supply to a carbonated beverage dispenser shall be protected against backflow with an integral 
backflow preventer conforming to ASSE 1032 or an air gap. Carbonated beverage dispensers and carbon- 
ated beverage dispensing systems without an integral backflow preventer conforming to ASSE 1032 or an air 
gap shall have the water supply protected with a double check valve with atmospheric vent conforming to 
ASSE 1032. 

10.5.9 Protection from Fire Systems 

a. Potable water supplies to water-based fire protection systems, including but not limited to standpipes 
and automatic sprinkler systems, shall be protected from back-pressure and back-siphonage by one of the 
following testable devices: 



2006 National Standard Plumbing Code-Illustrated 



221 



1. double check fire protection backflow protection assembly - ASSE 1015 (DCF) 

2. double check detector fire protection backflow protection assembly - ASSE 1048 (DCDF) 

3. reduced pressure principle fire protection backflow prevention assembly - ASSE 1013 (RPF) 

4. reduced pressure detector fire protection backflow prevention assembly - ASSE 1047 (RPDF) 
EXCEPTIONS 

(1) ASSE 1024 dual check valves in residential sprinkler systems 

(2) ASSE 1024 dual check valves in limited area sprinkler systems 

(3) Where fire protection systems include a fire department connection, double check valve assembles shall 
not be permitted. 

(4) Where fire protection systems are filled with solutions that are considered to be health hazards as defined 
in Section 1.2, double check valve assemblies shall not be permitted. 

b. Whenever a backflow protection device is installed in a potable water supply to a fire protection system, the 
hydraulic design of the fire protection system shall account for the pressure drop through the backflow protection 
device. 

c. If backflow protection devices are retrofitted for an existing fire protection system, the hydraulics of the fire 
protection system shall be checked to verify that there is sufficient water pressure available for satisfactory 
operation of the fire protection system. 

10.5.1 Protection from Lawn Sprinklers and Irrigation Systems 

a. Potable water supplies to systems having no pumps or connections for pumping equipment, and no 
chemical injection or provisions for chemical injection, shall be protected from backflow by one of the follow- 
ing devices: 

1 . Atmospheric vacuum breaker 

2. Pressure vacuum breaker (PVB) 

3. Spill-resistant vacuum breaker (SVB) 

4. Reduced pressure backflow preventer assembly 

b. Where sprinkler and irrigation systems have pumps, connections for pumping equipment, auxiliary air 
tanks or are otherwise capable of creating back -pressure, the potable water supply shall be protected by the 
following type of device if the backflow device is located upstream from the source of back-pressure. 

1 . Reduced pressure backflow preventer assembly 

c. Where systems have a backflow device installed downstream from a potable water supply pump or a 
potable water supply pump connection, the device shall be one of the following: 

1 . Atmospheric vacuum breaker 

2. Pressure vacuum breaker (PVB) 

3. Spill-resistant vacuum breaker (SVB) 

4. Reduced pressure backflow preventer assembly 

d. Where systems include a chemical injector or any provisions for chemical injection, the potable water 
supply shall be protected by the following: 

1 . Reduced pressure backflow preventer assembly 

10.5.11 Domestic Water Heat Exchangers 

a. Heat exchangers used for heat transfer, heat recovery, or solar heating shall protect the potable water 
system from being contaminated by the heat transfer medium, in accordance with either subparagraph b or c 
below. 

b. Single-wall heat exchangers shall be permitted if they satisfy all of the following requirements: 

1. The heat transfer medium is either potable water or contains only substances that 
are recognized as safe by the U.S. Food and Drug Administration. 

2. The pressure of the heat transfer medium is maintained less than the normal minimum 
operating pressure of the potable water system. 



222 



2006 National Standard Plumbing Code-Illustrated 



EXCEPTION: Steam complying with subparagraph b.l. 

3. The equipment is permanently labeled to indicate that only additives recognized as 
safe by the FDA shall be used in the heat transfer medium, 
c. Double-wall heat exchangers shall separate the potable water from the heat transfer medium by 
providing a space between the two walls that is vented to the atmosphere. 

10.5.12 Hose Connections 

A pressure-type or atmospheric-type vacuum breaker or a permanently attached hose connection vacuum breaker 
shall protect hose bibbs, sill-cocks, wall hydrants and other openings with a hose connection. 
EXCEPTIONS: 

(1) Water heater and boiler drain valves that are provided with hose connection threads and that are intended 
only for tank or vessel draining shall not be required to be equipped with a backflow preventer. 

(2) This section shall not apply to water supply valves intended for connection to clothes washing machines 
where backflow prevention is otherwise provided or is integral with the machine. 

10.5.13 Protection for Special Equipment 

The water supply for any equipment or device that creates a cross-connection with the potable water 
supply shall be protected against backflow as required in Section 10.5. Such equipment and devices includes, 
but is not limited to, chemical dispensers, portable cleaning equipment, sewer and drain cleaning equipment, 
and dental pump equipment. 

a. Chemical Dispensing Systems 

Chemical dispensing systems with connections to the potable water distribution system shall protect the water 
distribution system from backflow in accordance with ASSE 1055. 

b. Portable Cleaning Equipment 

Where the water distribution system connects to portable cleaning equipment, the water supply system shall 
be protected against backflow in accordance with Section 1 0.5, which allows for an atmospheric vacuum breaker, 
pressure vacuum breaker, double check valve, or a reduced pressure principle assembly. 

EXCEPTION: Atmospheric vacuum breakers shall not be used where there are shutoff valves or other shutoff 
devices downstream or where they are subject to continuous flowing pressure for more than 1 2 hours at a time. 

c. Dental Pump Equipment 

Where the water distribution system connects to dental pumping equipment, the water supply system shall be 
protected against backflow in accordance with Section 10.5, which allows for an atmospheric vacuum breaker, 
pressure vacuum breaker, double check valve, or a reduced pressure principle assembly. 

EXCEPTION: Atmospheric vacuum breakers shall not be used where there are shutoff valves or other shutoff 
devices downstream or where they are subject to continuous flowing pressure for more than 12 hours at a time. 

10.6 WATER SERVICE 

10.6.1 Separation of Water Service and Building Sewer 

The water service pipe and building drain or building sewer shall not have less than one foot horizontal 
distance between the piping. See Figures 10.6.1 - A and - B 



2006 National Standard Plumbing Code-Illustrated 223 



BUILDING DRAIN OR BUILDING SEWER 



SUFFICIENT DEPTH 
FOR FREEZE PROTECTION 




NOTES: 

1 . Improvements in the integrity of underground drainage system pipe joints has permitted the separa- 
tion from potable water piping to be reduced to 12 inches. 

Figure 10.6.1 - A 

THE MINIMUM DISTANCE BETWEEN AN UNDERGROUND WATER SERVICE 

AND A BUILDING DRAIN OR BUILDING SEWER 



WATER SERVICE 




BUILDING DRAIN 
OR SEWER 

WATER SERVICE OVER ( PREFERRED ) 




BUILDING DRAIN 
OR SEWER 

WATER SERVICE UNDER ( PERMITTED ) 



NOTES: 

1 . The minimum clearance is 1 2 inches. 

2. Where possible, the water service should cross over the building drain or building sewer. 

3. If necessary, the water service can cross under the building drain or building sewer. 

4. The 1 2" minimum separation prevents direct contact between the pipe lines, even with considerable 
settlement. 



Figure 10.6.1 - B 

CROSSING A WATER SERVICE OVER (OR UNDER) 

A BUILDING DRAIN OR BUILDING SEWER 



224 



2006 National Standard Plumbing Code-Illustrated 



10.6.2 Water Service Near Sources of Pollution 

Potable water service piping shall not be located in, under, or above cesspools, septic tanks, septic tank 
drainage fields, or drainage pits. A separation often feet shall be maintained from such systems. When a 
water line parallels or crosses over or under a sewer, a minimum clearance of 12 inches in all directions shall 
be maintained. See Figure 10.6.2 



CESSPOOL, SEPTIC TANK, 
SEPTIC TANK DRAINAGE FIELD, 
AND DRAINAGE PIT 



MINIMUM 
CLEARANCE 



10 FEET 

MINIMUM 



i- 



POTABLE WATER SERVICE PIPING 



Figure 10.6.2 

MINIMUM CLEARANCE BETWEEN A WATER SERVICE PIPE 

AND SOURCES OF CONTAMINATION 



10.6.3 Stop-and-Waste Valves Prohibited 

Combination stop-and-waste valves or cocks shall not be installed underground in water service piping. 



Comment: Open waste outlets on underground water service shutojf valves would permit ground water 
to contaminate the potable water supply. 



10.6.4 Water Service Pipe Sleeves 

Pipe sleeves shall be provided where water service pipes penetrate foundation walls or floor slabs to protect 
against corrosion of the pipe and allow clearance for expansion, contraction and settlement. The sleeve shall 
form a watertight bond with the wall or floor slab. The annular space between the pipe and the sleeve shall 
be resiliently sealed watertight. Where water service piping is plastic, the wall sleeve shall be not less than 
five feet long extended outside beyond the wall. See Figure 10.6.4 



2006 National Standard Plumbing Code-Illustrated 



225 



FLOOR SLAB 




PLASTIC WATER 
SERVICE PIPE 



5 FEET MINIMUM 



FLOOR SLAB 



SEE NOTE 2 



&&&&&&x*L 



-WATER SERVICE PIPE SLEEVE 
- SEE NOTE 1 

- METALLIC WATER SERVICE PIPE 



■ SEE NOTE 2 



NOTES 

1 . The pipe sleeve must be sealed watertight to the wall or floor slab. 

2. A 1/2" minimum annular space around the water pipe, between the pipe and the sleeve is required 
and must be sealed watertight. 

3. Sleeves for plastic water service pipe must extend outside beyond foundation walls to undisturbed 
earth and be at least 5 feet long. 

Figure 10.6.4 
WATER SERVICE PIPE SLEEVES FOR METALLIC AND PLASTIC PIPING 

10.6.5 Water Service Sizing 

The water service pipe shall be of sufficient size to furnish water to the building in the quantities and at the 
pressures required elsewhere in this Code. The pipe size shall not be less than 3/4 inch nominal. 



10.7 WATER PUMPING AND STORAGE EQUIPMENT 

10.7.1 Pumps and Other Appliances 

Water pumps, filters, softeners, tanks and other appliances and devices used to handle or treat potable 
shall be protected against contamination as per Section 10.5. 



water 



226 



2006 National Standard Plumbing Code-Illustrated 



10.7.2 Prohibited Location of Potable Supply Tanks 

Potable water gravity tanks or manholes of potable water pressure tanks shall not be located directly under 
any soil or waste piping. 

10.8 WATER PRESSURE BOOSTER SYSTEMS 

10.8.1 Water Pressure Booster Systems Required 

a. When the water pressure in the public water main or individual water supply system is insufficient to 
supply the potable peak demand flow to plumbing fixtures and other water needs freely and continuously with 
the minimum pressure and quantities specified in Section 10. 14.3, or elsewhere in this Code, and in accor- 
dance with good practice, the rate of supply shall be supplemented by one of the following methods: 

1 . An elevated water tank. 

2. A hydro-pneumatic pressure booster system. 

3. A water pressure booster pump. 

10.8.2 Reserved 

1 0.8.3 Overflows for Water Supply Tanks 

Gravity or suction water supply tanks shall be provided with an overflow having a diameter not less than that 
shown in Table 10.8.3. The overflow outlet shall discharge above and within not less than 6 inches of a roof 
or roof drain, floor or floor drain, or over an open water-supplied fixture. The overflow outlet shall be covered 
by a corrosion-resistant screen of not less than 16 x 20 mesh to the inch and by 1/4 inch hardware cloth, or it 
shall terminate in a horizontally installed 45° angle-seat check valve. Drainage from overflow pipes shall be 
directed so as not to freeze on roof walkways. See Figure 10.5.7 

Table 10.8.3 
SIZES 1 OF OVERFLOW PIPES FOR WATER SUPPLY TANKS 



Maximum Capacity Diameter of Maximum Capacity Diameter 
of Water Supply Line Overflow Pipe of Water Supply Line Overflow Pipe 
to Tank (Inches ID) to Tank (Inches ID) 

0-13 gpm 1-1/2 356-640 gpm 5 

14-55 gpm 2 641-1040 gpm 6 

56-100 gpm 2-1/2 over 1040 gpm 8 

101-165 gpm 3 
166-355 gpm 4 

1 Computed by the method of NBS Mono. 3 1, for vertical pipes flowing not greater than 1/2 full at terminal velocity. (1/3 full for 1-1/2 in. 
pipe). 

10.8.4 Covers 

All water supply tanks shall be covered to keep out unauthorized persons, dirt, and vermin. The covers of 
gravity tanks shall be vented with a return bend vent pipe having an area not less than the area of the down 
feed riser pipe and the vent shall be screened with corrosion resistant screen having not less than 14 and not 
more than 20 openings per linear inch. See Figure 10.5.7 

1 0.8.5 Potable Water Inlet Control and Location 

Potable water inlets to gravity tanks shall be controlled by a ball cock or other automatic supply valve so 
installed as to prevent the tank from overflowing. The inlet shall be terminated so as to provide an accepted 
air gap but in no case less than 4 inches above the overflow.. See Figure 10.5.7 



2006 National Standard Plumbing Code-Illustrated 227 



10.8.6 Tank Drain Pipes 

Each tank shall be provided at its lowest point with a valved pipe to permit emptying the tank. See Figure 
10.5.7 

1 0.8.7 Low Pressure Cut-Off Required on Booster Pumps 

Booster pumps shall be protected by a low pressure cut-off switch to shut-off the pump(s) if the suction 
pressure drops to an unsafe value. 

10.8.8 Pressure Tanks — Vacuum Relief 

All water pressure tanks shall be provided with a vacuum relief valve at the top of the tank that will operate 
up to a maximum water pressure of 200 psi and to maximum water temperatures of 200°F. The minimum size 
of such vacuum relief valves shall be 1/2 inch. 

10.8.9 Pressure Tanks — Pressure Relief 

All water pressure tanks shall be provided with approved pressure relief valves set at a pressure not in excess 
of the tank working pressure. 

10.9 FLUSHING AND DISINFECTING POTABLE WATER SYSTEMS 

10.9.1 Flushing 

The water service piping and distribution piping to all fixtures and outlets shall be flushed until the water runs 
clear and free of debris or particles. Faucet aerators or screens shall be removed during flushing operations. 

10.9.2 Disinfecting 

a. Where required by the Authority Having Jurisdiction, the water service piping and the hot and cold water 
distribution piping in new or renovated potable water systems shall be disinfected after flushing and prior to 
use. The procedure used shall be as follows or an approved equivalent: 

1 . All water outlets shall be posted to warn against use during disinfecting operations. 

2. Disinfecting shall be performed by persons experienced in such work. 

3. The water supply to the piping system or parts thereof being disinfected shall be valved-off from the 
normal water source to prevent the introduction of disinfecting agents into a public water supply or portions of 
a system that are not being disinfected. 

4. The piping shall be disinfected with a water-chlorine solution. During the injection of the disinfecting 
agent into the piping, each outlet shall be fully opened several times until a concentration of not less than 50 
parts per million chlorine is present at every outlet. The solution shall be allowed to stand in the piping for at 
least 24 hours. 

5. An acceptable alternate to the 50 ppm/24-hour procedure described in Section 1 0.9.2.d shall be to 
maintain a level of not less than 200 parts per million chlorine for not less than three hours. If this alternate 
procedure is used, the heavily concentrated chlorine shall not be allowed to stand in the piping system for 
more than 6 hours. Also, special procedures shall be used to dispose of the heavily concentrated chlorine in an 
environmentally acceptable and approved manner. 

6. At the end of the required retention time, the residual level of chlorine at every outlet shall be not less 
than five parts per million. If the residual is less than five parts per million, the disinfecting procedure shall be 
repeated until the required minimum chlorine residual is obtained at every outlet. 

7. After the required residual chlorine level is obtained at every outlet, the system shall be flushed to 
remove the disinfecting agent. Flushing shall continue until the chlorine level at every outlet is reduced to that 
of the incoming water supply. 



22o 2006 National Standard Plumbing Code-Illustrated 



8. Any faucet aerators or screens that were removed under Section 10.9.1 shall be replaced 
9 A certification of performance and laboratory test report showing the absence of coliform organisms 
shall be submitted to the Authority Having Jurisdiction upon satisfactory completion of the disinfecting opera- 
tions. & ' 

10.10 WATER SUPPLY SYSTEM MATERIALS 

See Section 3.4.3. 

10.11 ALLOWANCE FOR CHARACTER OF SOIL AND WATER 

When selecting the material and size for water service supply pipe, tube, or fittings, due consideration shall be 
given to the action of the water on the interior of the pipe and of the soil, fill or other materia] on the exterior of the 
pipe. (Appendix B gives recommendations concerning allowances to be made in sizing water piping because of the 
properties of the water.) 



Comment: The chemical composition of the service water should be considered when selecting the water 
service pipe material. Refer to Appendix Section B.2.3. The aggressive nature of the soil or Jill material 
around the water service pipe should be evaluated when considering if additional corrosion protection is 
need for the exterior surfaces of the pipe. 



10.12 WATER SUPPLY CONTROL VALVES 

10.12.1 Curb Valve 

On the water service from the street main to the building, an approved gate valve or ground key stopcock or 
ball valve shall be installed near the curb line between the property line and the curb. This valve or stopcock 
shall be provided with an approved curb valve box. See Figure 1.2.82 

10.12.2 Building Valve 

The building water service shall be provided with a readily accessible gate valve with bleed or other full-way 
valve with bleed located inside the building near the point where the water service enters. When the building 
water service enters a crawl space, the building valve shall be readily accessible. Where there are two or 
more water services serving one building, a check valve shall be installed on each service in addition to the 
above valves. See Figure 1.2.82 

10.12.3 Water Supply Tank Valve 

A shutoff valve shall be provided at the outlet of any tank serving as a water supply source, either b V gravity 
or pressure. See Figure 10.5.7 ' 

10.12.4 Valves in Dwelling Units 

a. Except as defined in 10.12.4.b, c and d, individual fixture shutoff or stop valves shall be provided for water 
closets, lavatories, kitchen sinks, laundry trays, bar sinks, bidets, clothes washing machines, sill cocks wall 
hydrants, appliances and equipment connected to the water supply system. Valves for fixtures, appliances and 
equipment shall be accessible without having to move the appliance or equipment 

EXCEPTION: Valves for ice makers 

b. Shutoff valves shall be provided for each powder room or bathroom group unless all fixtures within the 
room or group have individual fixture shutoff or stop valves. 

c. In a single dwelling unit, two bathrooms or powder rooms installed back-to-back or one directly above the 



2006 National Standard Plumbing Code-Illustrated „„ 



other may be considered as a single group and shall be permitted to have one set of shutoff valves. If two 
such rooms are not piped as a single group, separate shutoff valves shall be provided for each room or group. 

d. In multi-dwelling units, one or more shutoff valves shall be provided in each dwelling unit so that the water 
supply to any plumbing fixture or group of fixtures in that dwelling unit can be shut off without stopping the 
water supply to fixtures in other dwelling units. These valves shall be accessible in the dwelling unit that they 
control. 

e . Self-piercing and needle-type saddle valves shall be prohibited. 
See Figures 10.12.4-A and-B 




REFRIGERATOR 
WITH ICE MAKER 



SILL COCK OR 
WALL HYDRANT 



WATER SERVICE - 



NOTES 
1. 
2. 
3. 



6. 



The building shutoff valve must be a full-way type with a bleed to drain the piping within the building . 

The water heater shutoff valve must not be a globe valve. 

Additional shutoff valves can be provided to isolate the water heater and branches of the water 

distribution piping. 

Shutoff valves for powder rooms and bathroom groups are not required if all fixtures within the group 

have individual shutoff valves. One set of shutoff valves can serve two bathroom groups if they are 

piped as one group of fixtures without separate branch pipes for each group. 

Water closets and lavatories usually have individual supply stop valves where the fixture supply tube 

connects to the fixture branch supply pipe. 

Where manifold-type parallel water distribution systems are used, the individual fixture shutoff valves 

are located on the manifold. 



Figure 10.12.4 - A 
REQUIRED WATER SHUTOFF VALVES IN SINGLE DWELLING UNITS 



230 



2006 National Standard Plumbing Code-Illustrated 



KITCHEN SINK 

VJLJ 



KITCHEN SINK 






WC - WATER CLOSET 
LAV - LAVATORY 
® -REQUIRED SHUTOFF VALVE 



WC 



LAV 



TUB 



BATHROOM 
GROUP 



WC LAV 



/ 



"W" 



TUB 



BATHROOM 
GROUP 

. RISER VALVES 



■ INDIVIDUAL 
DWELLING UNIT 



• INDIVIDUAL 
DWELLING UNIT 



NOTES 

1 . Riser shutoff valves are required where risers serve dwelling units on two or more floors. 

2. Shutting off a fixture in one dwelling unit must not stop the water supply to a fixture in another 
dwelling unit. 

3. Main shutoff valves are not mandatory for each dwelling unit if all fixtures within the unit have a 
means of shutoff. 

4. Shutoff valves for powder rooms and bathroom groups are not mandatory if all fixtures within the 
group have individual shutoff valves. One set of shutoff valves can serve two bathroom groups within 
the same dwelling unit if they are piped as one group of fixtures without separate branch pipes for 
each group. 

5. Water closets and lavatories usually have individual supply stop valves where the fixture supply tube 
connects to the fixture branch supply pipe. 

6. All shutoff valves for the fixtures in each dwelling unit must be accessible within the dwelling unit 
that they serve. 

Figure 10.12.4 - B 
REQUIRED WATER SHUTOFF VALVES IN MULTI-DWELLING UNITS 



10.12.5 Riser Valves 

Shutoff valves(s) shall be provided for isolating each water supply riser serving fixtures on two or more 

floors. 

EXCEPTION: Risers within individual dwelling units. See Figure 1.2.49 



2006 National Standard Plumbing Code-Illustrated 



231 



10.12.6 Individual Fixture Valves 



In a building used or intended to be used for other than dwelling purposes, the water distribution pipe to each 
fixture or other piece of equipment shall be provided with a valve or fixture stop to shut off the water to the 
fixture or to the room in which it is located. These valves shall be accessible. Sill cocks and wall hydrants 
shall be separately controlled by a valve inside the building. 



Comment: In buildings or portions thereof that are used for other than dwelling purposes, each fixture 
or equipment connection must have an individual shutoff means. Shutoff valves in such systems cannot 
shutoffa group of fixtures that do not have individual shutoff means. The guest rooms in hotels and 
motels are considered to be dwelling units. 



10.12.7 Water Heating Equipment Valve 

A shutoff valve shall be provided in the cold water supply to each water heater. If a shutoff valve is also 
provided in the hot water supply from the heater, it shall not isolate any safety devices from the heater or 
storage tank. Shutoff valves for water heaters shall be the gate, ball, plug, or butterfly type. See Figure 
10.12.7 



COLD 



OPTIONAL HOT WATER 
SHUTOFF VALVE 



DRAIN VALVE 




COLD WATER 
SHUTOFF VALVE 



RELIEF VALVE 



RELIEF VALVE DISCHARGE PIPE 

TO APPROVED POINT OF DISCHARGE 



DIP TUBE 



NOTES: 

1 . The cold water shutoff valve permits the water heater to be serviced or replaced, but requires that 
the hot water distribution piping be drained. 

2. The optional hot water shutoff valve permits the water heater to be serviced or replaced without 
draining the hot water distribution piping. 

3. The water heater relief valve must not be isolated from the water heater tank by any shutoff valves. 

4. Water heater shutoff valves must be the full-flow type. Globe valves are not permitted. 

Figure 10.12.7 
WATER HEATER SHUTOFF VALVE(S) 



232 



2006 National Standard Plumbing Code-Illustrated 



10.12.8 Meter Valve 

A gate valve or other full- way valve shall be installed in the line on the discharge side of each water meter. 
The valve shall not be less in size than the building water service pipe. 
See Figures 10.12.8-A and-B 



ROADWAY 



METER FRAME & COVER 

SIDEWALK 



CORPORATION COCK 




WATER SERVICE 
TO BUILDING 



- PUBLIC WATER MAIN 



NOTES: 

1 . The stop valve on the inlet side of the water meter is normally provided by the water service utility, 
can be the curb valve required by Section 10.12.1. 

2. The distinction between small and large water services is dictated by the Authority Having Jurisdic- 
tion. For small water services, the shutoff valve on the outlet side of the water meter can be the 
building valve required by Section 10.12.2. See Figure 10. 12.8 -B for largerwater services. 

3. Adapter fittings are required where the pipe material for the water service to the building is different 
from the pipe material provided by the water utility. 



It 



Figure 10.12.8 - A 
METER SHUTOFF VALVES IN A SMALL WATER SERVICE 



2006 National Standard Plumbing Code-Illustrated 



233 



• METER VAULT 



WATER SUPPLY FROM 
PUBLIC WATER MAIN 




WATER METER 
INLET SHUTOFF VALVE 



OUTLET SHUTOFF VALVE 



WATER SERVICE 
TO BUILDING 



NOTES: 

1 . The shutoff valve on the inlet side of the water meter is normally provided by the water utility. 

2. The bypass valve is optional. It can be used to provide continuous water service while the meter is 
being repaired or replaced. 

3. The bypass valve and shutoff valve on the meter outlet permit the meter to be repaired or replaced 
without interrupting the water service to the facility. 

Figure 10.12.8 - B 
METER SHUTOFF VALVES IN A LARGE WATER SERVICE 



10.12.9 Valve Accessibility 

Water supply control valves shall be placed so as to be accessible for service and maintenance. 



Comment: Access to water supply shutoff valves can require the use of tools to remove access panels or 
doors. 



10.13 FLEXIBLE WATER CONNECTORS 

Flexible water connectors exposed to continuous pressure shall conform to ASME Al 12.18.6. Access shall be 
provided to all flexible water connectors. 

10.14 MINIMUM REQUIREMENTS FOR WATER DISTRIBUTION 

SYSTEMS 

10.14.1 Maximum Velocity (See Appendix B.6) 

Water distribution piping within buildings shall be sized for a maximum velocity of 8 feet per second at the 
design flow rate unless the pipe manufacturer's sizing recommendations call for the maximum velocity to be 
less than 8 feet per second. 



234 



2006 National Standard Plumbing Code-Illustrated 



10.14.2 Size of Individual Fixture Supply Branches 

a. Individual fixture supply branch pipe sizes shall be based on the minimum available flowing water 
pressure at the point of connection to the water distribution system, any elevation difference between that 
connection and the fixture, and the allowable pressure loss in the fixture supply branch. The minimum fixture 
supply branch pipe sizes shall be as indicated in Table 10.14.2A. For design purposes, the required pressure at 
each fixture inlet shall be 1 5 psig rmmmum with flow for all fixtures, except 20 psig flowing for flushometer 
valves on siphon jet water closets and 25 psig flowing for flushometer valves on blowout water closets and 
blowout urinals. Flushometer tank (pressure assisted) water closets require a minimum of 25 psig static 
pressure. The following water flow rates shall be used for the purpose of sizing individual fixture supply 
branch pipes: FF y 

5.0 gpm for hose bibbs and wall hydrants; 

4.0 gpm for bath faucets and clothes washers; 

0.75 gpm for drinking fountains and water coolers; 

2.5 gpm for sink faucets; 

2.5 gpm for showers; 

1 .5 gpm for lavatory faucets; 

3.0 gpm for water closets other than the flushometer valve type; 

12.0 gpm for flushometer valve urinals; 

30.0 gpm for flushometer valve water closets 
b. Fixture supply branches shall extend from the distribution system to within 30 inches of the point of 
connection to the fixture or device served and be within the same area and physical space as the point of 
connection to the fixture or device. Fixture supply tubes and flexible water connectors shall be not less than 
the size recommended by the manufacturer of the fixture, faucet, appliance or device served. 

10.14.3 Sizing Water Distribution Piping 

a. The supply demand in gallons per minute in the building hot and cold water distribution system shall be 
determined on the basis of the load in terms of water supply fixture units (WSFU) as shown in Table 
10. 14.2A and the relationship between the load in WSFU and the supply demand in gallons per minute (gpm) 
as shown in Table 10.14.2B. For fixtures having both hot water and cold water connections, the separate hot 
water and cold water loads shall be taken as 75% of the listed fixture unit value 

b. Main risers and branches of the water distribution system shall be sized based on the minimum available 
water pressure at the source, any elevation differences between the source and the fixtures, pressure losses 
in the distribution system, and the pressure (with flow) required at each connection of the fixture supply 
branches. rK J 

10.14.4 Inadequate Water Pressure 

Whenever water pressure from the street main or other sources of supply is insufficient to provide flow 
pressures at fixture outlets as required under Section 10. 14.3, a booster pump and pressure tank or other 
approved means shall be installed on the building water supply system. 



2006 National Standard Plumbing Code-Illustrated 



235 



Table 10. 14.2 A 

WATER SUPPLY FIXTURE UNITS (WSFU) AND MINIMUM FIXTURE BRANCH 

PIPE SIZES 


HEAVY-USE ASSEMBLY 


TYPE OF FIXTURES OTHER THAN DWELLING UNITS 




SERVING 3 OR MORE DWELLING UNITS 




INDIVIDUAL DWELLING UNITS 




MINIMUM BRA.NCH PIPE SIZE 




JJATHKOOM CROITS HAVING 1.6 t-t'f WATER 

ci osfts oj iikr i n v>: the ki.i suometer 

V MAT. H pi 












fn^bath oT'Powder Room ' 












1 Bathroom Group 




5.0 


3.5 






1 V 2 Bathrooms 




6.0 








2 Bathrooms 




7.0 








2 V 2 Bathrooms 




8.0 








3 Bathrooms 




9.0 








Each Additional 'A Bath 




0.5 








Each Additional Bathroom Group 




1.0 








B.VIHKOO.M GROl PS HAVING 3 5 GPF 

c:R,wnv-i vvk w vnu ci.oskts 


lllllfllll 










Half-bath or Powder Room 




4.0 


3.0 






1 Bathroom Group 




6.0 


5.0 






I V 2 Bathrooms 




8.0 








2 Bathrooms 




10. 








2 V 2 Bathrooms 




11.0 








3 Bathrooms 




12.0 








Each Additional V 2 Bath 




0.5 








Each Additional Bathroom Group 




1 .0 








BATH GROUP (1.6 GPF Flushometer Valve) 






iillii 






BATH GROUP (3.5 GPF Flushometer Valve) 




\ - 


..- 






KITCHEN GROUP (Sink and Dishwasher) 




2.0 


j 5 






LAUNDRY GROUP (Sink and Clothes Washer) 




5.0 


3 .0 







236 



2006 National Standard Plumbing Code-Illustrated 



Table 10.14.2A (Continued) 

WATER SUPPLY FIXTURE UNITS (WSFU) AND MINIMUM FIXTURE BRANCH 

PIPE SIZES 


HEAVY-USE ASSEMBLY 


TYPE OF FIXTURES OTHER THAN DWELLING UNITS 




SERVING 3 OR MORE DWELLING UNITS 




INDIVIDUAL DWELLING UNITS 




MINIMUM BRANCH PIPE SIZE 




; n n i vi m.:,\ i . n xi i; rks 












Bathtub or Combination Bath/Shower 


7," 


4.0 


3.5 






Bidet 


V 


1.0 


0.5 






Clothes Washer, Domestic 


V 2 " 


4.0 


2.5 


4.0 




Dishwasher, Domestic 


V," 


1.5 


1.0 


1.5 




Drinking Fountain or Watcrcooler 


V 






0.5 


0.75 


Hose Bibb 


V 2 " 


2.5 


2.5 


*? c 




Hose Bibb, Each Additional 


7 2 " 


1.0 


1.0 


1.0 




Kitchen Sink, Domestic 


'/:" 


1.5 


1.0 


1.5 




Laundry Sink 


'/," 


2.0 


1.0 


2.0 




Lavatory 


V 


1.0 


0.5 


1.0 


1.0 


Service Sink or Mop Basin 


'/:" 






3.0 




Shower 


'2 


2.0 


2.0 


2.0 




Shower, Continuous Use 


V 2 " 






5.0 




Urinal, 1.0 GPF 


3 / 4 " 






4.0 


5.0 


Urinal, Greater Than 1.0 GPF 


V 






5.0 


6.0 


Water Closet, 1.6 GPF Gravity Tank 


V," 


2.5 


2.5 


2.5 


4.0 


Water Closet, 1.6 GPF Flushometcr Tank 


V 


2.5 


2.5 


2.5 


3.5 


Water Closet, 1.6 GPF Flushometer Valve 


1 


5.0 


5.0 


5.0 


8.0 


Water Closet, 3.5 GPF Gravity Tank 


V 2 " 


3.0 


3.0 


5.5 


7.0 


Water Closet, 3.5 GPF Flushometer Valve 


1 


7.0 


7.0 


8.0 


10.0 


Whirlpool Bath or Combination Bath/Shower 


V 2 " 


4.0 


4.0 







NOTES: 

1. A Bathroom Group, for the purposes of this Table, consists of not more than one water closet, up to two lavatories, and either one bathtub, 
one bath/shower combination, or one shower stall. Other fixtures within the bathing facility shall be counted separately to determine the total 
water supply fixture unit load. 

2. A Half-Bath or Powder Room, for the purposes of this Table, consists of one water closet and one lavatory. 

3. For unlisted fixtures, refer to a listed fixture having a similar flow and frequency of use. 

4. The listed fixture unit values for Bathroom Groups and Individual Fixtures represent their load on the cold water service. The separate cold 
water and hot water fixture unit values for fixtures having both cold and hot water connections shall each be taken as 3/4 of the listed total value 
for the individual fixture.. 

5. When WSFU values are added to determine the demand on the water distribution system or portions thereof, round the sum to the nearest 
whole number before referring to Table 10.14.2B for the corresponding gallons per minute (gpm) flow. WSFU values of 0.5 or more should be 
rounded up to the next higher whole number (9.5 = 10 WSFU). Values of 0.4 or less should be rounded down to the next lower whole number (9.4 
= 9 WSFU). 

6. The listed minimum supply branch pipe sizes for individual fixtures arc the nominal (I.D.) pipe size in inches. 

7. "Other Than Dwelling Units" applies to business, commercial, industrial, and assembly occupancies other than those defined under "Heavy- 
Use Assembly." Included are the public and common areas in hotels, motels, and multi-dwelling buildings. 

8. "Heavy-Use Assembly" applies to toilet facilities in occupancies that place heavy, but intermittent, time-based demands on the water 
supply system, such as' schools, auditoriums, stadiums, race courses, transportation terminals, theaters, and similar occupancies where queuing is 
likely to occur during periods of peak use. 

9. For fixtures or supply connections likely to impose continuous flow demands, determine their required flow in gallons per minute (gpm) and 
add it separately to the demand (in gpm) for the distribution system or portion thereof. 



2006 National Standard Plumbing Code-Illustrated 



237 









Table 10.14.2B 








TABLE FOR CONVERTING DEMAND IN WSFU TO GPM 1 






GPM 


GPM 




GPM 


GPM 


WSFU 


Flush Tanks 2 


Flush Valves 3 


WSFU 


Flush Tanks 2 


Flush Valves 3 


3 


3 




120 


49 


74 


4 


4 




140 


53 


78 


5 


4.5 


22 


160 


57 


83 


6 


5 


23 


180 


61 


87 


7 


6 


24 


200 


65 


91 


8 


7 


25 


225 


70 


95 


9 


7.5 


26 


250 


75 


100 


10 


8 


27 


300 


85 


110 


11 


8.5 


28 


400 


105 


125 


12 


9 


29 


500 


125 


140 


13 


10 


29.5 


750 


170 


175 


14 


10.5 


30 


1000 


' 210 


210 


15 


11 


31 


1250 


240 


240 


16 


12 


32 


1500 


270 


270 


17 


12.5 


33 


1750 


300 


300 


18 


13 


33.5 


2000 


325 


325 


19 


13.5 


34 


2500 


380 


380 


20 


14 


35 


3000 


435 


435 


25 


17 


38 


4000 


525 


525 


30 


20 


41 


5000 


600 


600 


40 


25 


47 


6000 


650 


650 


50 


29 


51 


7000 


700 


700 


60 


33 


55 


8000 


730 


730 


80 


39 


62 


9000 


760 


760 


100 


44 


68 


10,000 


790 


790 



NOTES: 

1. This table converts water supply demands in water supply fixture units (WSFU) to required water flow in gallons per minute (GPM) 
for the purpose of pipe sizing. 

2. This column applies to portions of piping systems where the water closets are the flush tank type (gravity or pressure) or there are no 
water closets, and to hot water piping. 

3. This column applies to portions of piping systems where the water closets are the flush valve type. 

10.14.5 Variable Street Pressures 

Where street water main pressures fluctuate, the building water distribution system shall be designed for the 
minimum pressure available. 



238 



2006 National Standard Plumbing Code-Illustrated 



10.14.6 Excessive Pressures 

a. Approved pressure reducing valves complying with ASSE 1003 shall be provided if required to limit the 
water supply pressure at any fixture appliance, appurtenance, or outlet to not more than 80 psi under no-flow 
conditions. 

b. The requirement of Section 10. 14.6.a above shall not prohibit supply pressures higher than 80 psi to 
water pressure booster systems under Section 10.14.4 or in high pressure distribution systems, provided that 
the pressure at the fixtures served is subsequently reduced to 80 psi maximum. Where operating water 
pressures exceed 80 psi, the working pressure rating of materials and equipment shall be suitable for the 
maximum pressure that may be encountered, including temporary increases or surges. 

c. Where pressure reducing valves are installed and the downstream piping is not rated for the maximum 
upstream pressure, a pressure relief valve shall be installed downstream from the pressure reducing valve. 
The relief valve shall be set not higher than the working pressure rating of the downstream piping and sized 
for not less than the flow capacity of the pressure reducing valve. Relief valves shall discharge in accordance 
with Sections 10.16.6a, b, c, and d. 
See Figures 10.14.6-A and-B 

SUPPLY PRESSURE TO FIXTURES 
REDUCED TO 80 P.S.I. MAX. 



BUILDING VALVE 
(Section 10.12.2) 




PRESSURE RELIEF VALVE 
(IF REQUIRED) 



PRESSURE 
REDUCING VALVE 
(Section 10.14.6) 



TO APPROVED 
POINT OF 
DISCHARGE 



SUPPLY PRESSURE 
GREATER THAN 80 psi 



NOTES: 

1. Example: A pressure booster pump is required to deliver domestic water to the 18th floor. 

2. The 1st, 2nd, and 3rd Floors are supplied with street pressure and a separate hot water heater. 

3. Without pressure reducing valves, the water supply pressure on the 4th through 13th Floors would exceed 80 psig. 

4. Generally, up to five floors can be zoned with one set of pressure reducing valves without having excessive pressure 
differences between the top and bottom floors of the zone. 

5. The pressure in the hot water recirculation line is essentially the same as in the adjacent hot water supply riser. 

6. The diagram shows only the hot water riser recirculated. If hot water must be circulated from the individual floors, pressure 
booster pumps would be required to pump the recirculated water from each reduced pressure zone back into the higher-pressure 
return riser (the downcomer). 



Figure 10.14.6 - A 

INSTALLATION OF A WATER PRESSURE REDUCING VALVE 

WHERE THE WATER SUPPLY PRESSURE EXCEEDS 80 PSIG 



2006 National Standard Plumbing Code-Illustrated 



239 



±. 



-M-cw—^ 



-^ CKhHW f- 

\ ' 

INSERT B 



HOT WATER 
RECIRCULATION 



1 



/ PRV \ 

—+-{xj — pijp-HW-/- 
\ 



See Note 6 ■ 



DOMESTIC WATER 
BOOSTER PUMP 



WATER 
SUPPLY 



\ B J 



w 




18THFLOOR 
17 TH FLOOR 
16 TH FLOOR 
15 TH FLOOR 
14 TH FLOOR 



13 TH FLOOR 
12 TH FLOOR 
11TH FLOOR 

10 TH FLOOR 
9 TH FLOOR 



8 TH FLOOR 
7 TH FLOOR 
6 TH FLOOR 
5 TH FLOOR 
4 TH FLOOR 



NOTES: 



1. Example: A pressure booster pump is required to deliver domestic water to the 18th floor. 

2. The 1st, 2nd, and 3rd Floors are supplied with street pressure and a separate hot water heater. 

3. Without pressure reducing valves, the water supply pressure on the 4th through 13th Floors would 
exceed 80 psig. 

4. Generally, up to five floors can be zoned with one set of pressure reducing valves without having 
excessive pressure differences between the top and bottom floors of the zone. 

5. The pressure in the hot water recirculation line is essentially the same as in the adjacent hot water 
supply riser. 

6. The diagram shows only the hot water riser recirculated. If hot water must be circulated from the 
individual floors, pressure booster pumps would be required to pump the recirculated water from 
each reduced pressure zone back into the higher-pressure return riser (the downcomer). 



Figure 10.14.6 - B 
ONE POSSIBLE ARRANGEMENT OF PRESSURE REDUCING VALVES 

IN A HIGH-RISE BUILDING 



10.14.7 Water Hammer 

a. Approved water hammer arresters, complying with ANSI/ASSE 1010, shall be installed on water 
distribution piping in which quick closing valves are installed. 

EXCEPTION: Single lever faucets, domestic clothes washers, and domestic dishwashers. 

b. Water hammer arresters shall be placed as close as possible to the quick acting valve, at the end of long 
piping runs, or near batteries of fixtures. 

c. Arresters shall be accessible for replacement. See Figure 10.14.7 



240 



2006 National Standard Plumbing Code-Illustrated 




PRESSURIZED 
AIR / GAS 
CUSHION 



DIAPHRAGM 
TYPE 



CONNECTION TO 
WATER PIPING 




"O" - RING SEAL 



PISTON 
TYPE 



NOTES: 

1. 
2. 



5. 



Water hammer arresters should be sized and installed according to the manufacturer's instructions 
PDI Standard WH201 establishes PDI Sizes "A" through "F" with recommendations on the number' 

of fixture units served by each size. Most manufacturers rank their products to the PDI Sizes 
Water hammer arrestors can be installed vertically or horizontally. They should be installed on the 

run of a tee fitting so that the unobstructed shock path is directly into the water hammer arrester 

See Figure 1.2.3. 

The number of elbows upstream from a water hammer arrestor should be minimized because thev 
create points of shock before the arrestor. 

Water hammer arrestors must be accessible and have a means of shutoff to permit replacement if 
necessary. The means of shutoff can be a shutoff valve for a group of fixtures. 

Figure 10.14.7 
WATER HAMMER ARRESTORS 



10.15 HOT WATER 

10.15.1 Hot Water Supply System 

In residences and buildings intended for human occupancy, hot water shall be supplied to all plumbing fixtures 
and equipment used for bathing, washing, culinary purposes, cleansing, laundry or building maintenance With 
the approval of the Authority Having Jurisdiction, tempered water supply systems may be installed in lieu of 
hot and cold water systems in buildings other than dwelling units. 

10.15.2 Temperature Maintenance Where Required 

a. Heated water distribution systems in buildings where developed length of heated water piping from the 
source of the heated water to the farthest fixture exceeds 100 feet shall maintain heated water temperature in 
all supply piping to within 25 feet of any heated water outlet. 

b. An approved electric heat tracing system shall be permitted to be used to satisfy the requirements of 
Section 10.15.2a. See Figure 10.15.2 



2006 National Standard Plumbing Code-illustrated 



241 



r- I . ' ' > 



25 FEET MAXIMUM 



DISTANCE TO FARTHEST HOT WATER OUTLET EXCEEDS 1 00 FEET 



CW 



CHECK 
VALVE - 
(NOTE 2) 



HOT 
WATER 
SOURCE 



COLD- 



HOT- 




t 



<h 



BALANCING COCKS (NOTE 3) 
RECIRCULATED LINE 



AQUASTAT(NOTEI) 



CIRCULATOR 



^ 



3-1 



^Z7 



TEMPERATURE MAINTAINED TO WITHIN 
25 FEET OF ALL HOT WATER OUTLETS - 1 



2. 



3. 



NOTES: 

1 . The aquastat or time/temperature controller starts the circulator when the recirculated line cools. 

The circulator stops when the line temperature rises. 

The check valve in the cold water supply to the hot water source keeps recirculated hot water from 

flowing into the cold water main due to pressure fluctuations in the distribution system. 

If the recirculation piping has more than one branch, balancing cocks in each branch permit the 

flows to be adjusted. 
4. A means of measuring the return temperature should be provided. 

Figure 10.15.2 
HOT WATER TEMPERATURE MAINTAINENCE BY RECIRCULATION 

10.15.3 Minimum Requirements for Hot Water Storage Tanks 

a. Hot water storage tanks shall be adequate in size, when combined with the B.T.U.H. input of the water 
heating equipment to provide the rise in temperature necessary. 

b. Water heaters and storage tanks shall be sized to provide sufficient hot water to provide both daily 
requirements and hourly peak loads of the occupants of the building. 

c. Storage tanks shall be protected against excessive temperatures and pressure conditions as specified in 
this Code. (See Sections 3.3.8 and 3.3.10) 

10.15.4 Drainage of Hot Water Storage Tanks 

Hot water storage tanks shall be equipped with a valve capable of draining the tank completely. See Figure 
10.12.7 



242 



2006 National Standard Plumbing Code-Illustrated 



10.15.5 Pressure Marking of Hot Water Storage Tanks 

Hot water storage tanks shall be permanently marked in an accessible place with the maximum allowable 
working pressure, in accordance with the applicable standard as listed in Table 3.1.3. 

10.15.6 Mixed Water Temperature Control 

a. Showers and Bath/ Shower Combinations: All showers and bath/shower combinations shall be provided with 
individual balanced pressure, thermostatic, or combination automatic compensating valves that comply with 
ASSE 1016 or ASME Al 12.18. 1/CSA B125.1. These valves shall include a means to limit the maximum 
discharge temperature of the water and shall be installed and field-adjusted in accordance with the manufacturer's 
instructions to a maximum of 1 20°F. No further mixing of water shall be permitted downstream of the automatic 
compensating valve. 

EXCEPTION: Where multiple showers are supplied by a one-pipe tempered water distribution system, the 
tempered water distribution system shall be controlled by an automatic temperature control mixing valve 
complying with ASSE 1 069. These valves shall include a means to limit the maximum discharge temperature of 
the water and shall be installed and field-adjusted in accordance with the manufacturer's instructions to a 
maximum of 120°F. No further mixing of water shall be permitted downstream of the automatic temperature 
controlled mixing valve. 

b. Bathtubs and Whirlpool Baths: The water discharged into bathtubs and whirlpool baths, with or without 
deck-mounted hand sprays, shall be controlled to a maximum temperature of 120°F by a device complying 
with CSA B125.3, ASSE 1070, ASME Bl 12. 18.1/CSA B125.1 or ASSE 1016. 

c. Public-Use Hand Washing Facilities: Water discharged from public-use hand washing facilities shall be 
limited to a maximum temperature of 1 10°F using a water temperature limiting device complying with ASSE 
1070. 

d. Commercial Hair/Shampoo Sink Sprays: The temperature of water discharged from commercial hair/ 
shampoo sink sprays shall be limited to a maximum of 1 10°F by a water temperature- limiting device comply- 
ing with ASSE 1070, ASME A112.18.1/CSA B125.1, or CSA B125.3. 

e. Temperature Actuated Flow Reduction (TAFR) Devices: Where temperature actuated flow reduction 
(TAFR) devices are installed to limit the maximum discharge temperature to 120°F for individual fixture 
fittings, such devices shall comply with ASSE 1062. These devices alone shall not supersede the other 
requirements of Section 10.15.6. 

f. In-Line Pressure Balancing Valves: Where m-line pressure balancing valves are installed to compensate 
for water pressure fluctuations to stabilize the temperature discharges from their individual faucet or fixture 
fitting, such devices shall comply with ASSE 1066. These devices shall be installed in an accessible location 
and alone shall not supersede the other requirements of Section 10.15.6 

g. Temperature-Actuated Mixing Valves: Where temperature-actuated mixing valves are installed to 
control the in-line hot water supply temperature in the water distribution system, they shall comply with 
ASSE 1017. Such devices shall be installed at the hot water source and alone shall not supersede the other 
requirements of Section 1 0. 1 5.6 for mixed water temperature control. 

h. The temperature control devices for water heaters and other hot water supply sources shall not be 
permitted to be used to meet this Section's requirements for mixed water temperature control. 

i. Alternative Methods: The use of a combination of water temperature control or limiting devices that 
comply with the standards listed in Table 3.1.3 and satisfy the performance requirements of Section 10.15.6 
shall be subject to the approval of the Authority Having Jurisdiction. 

10.15.7 ThermalExpansion Control 

Where a backflow prevention device, check valve or water pressure regulator is installed serving water 

heating equipment such that a closed system is created, a device for controlling thermal expansion shall be 

installed. 

EXCEPTION: Instantaneous water heaters. 



2006 National Standard Plumbing Code-illustrated 243 



10.15.8 Plastic Piping 

a. Plastic piping used for hot water distribution shall conform to the requirements of Section 3.4 and Table 
3.4. Piping shall be water pressure rated for not less than 100 psi at 180°F and 160 psi at 73°. 

NOTE: The working pressure rating for certain approved plastic piping materials varies depending on 
material composition, pipe size, wall thickness and method of joining. See Table 3.4.3. 

b. Plastic pipe or tube shall not be used downstream from instantaneous water heaters, immersion water heaters 
or other heaters not having approved temperature safety devices. 

c. Piping within six inches of flue or vent connectors shall be approved metallic pipe or tube. 

d. The normal operating pressure in water distribution piping systems utilizing approved plastic pipe or tube for 
hot water distribution shall be not more than 80 psi. Where necessary, one or more pressure reducing valves shall 
be provided to regulate the hot and cold water supply pressure to not more than 80 psi. 

e. The pressure in the hot water distribution piping shall be limited by a pressure relief valve set no higher than 
listed in Table 1 0. 1 5 .8 for the particular plastic piping material. When the water heater is protected by apressure 
relief valve or combination pressure -temperature relief valve having a pressure setting higher than listed in Table 
10.15.8, a separate pressure relief valve shall be provided to protect the piping. The relief valve for the piping 
shall comply with Section 10.16.2 except that it shall be set no higher than listed in Table 10.15.8. Thermal 
expansion shall be controlled as required under Section 10.15.7. 



Table 10.15.8 

MAXIMUM PRESSURE RELIEF VALVE SETTINGS 

FOR PLASTIC HOT WATER DISTRIBUTION PIPING 


HW DISTRIBUTION 
PIPING MATERIAL 


MAX. RELIEF 
VALVE SETTING 


CPVC (ASTM D2846) 


lOOpsig 


CPVC(ASTMF441) 


lOOpsig 


CPVC (ASTM F442) 


lOOpsig 


PEX (ASTM F876) 


100 psig 


PEX (ASTM F877) 


lOOpsig 


PE-AL-PE (ASTM D 1282) 


lOOpsig 


PEX-AL-PEX (ASTM F1281) 


125 psig 


Composite High Temperature PE-AL-PE (ASTM D1335) 


150 psig 


Composite High Temperature PEX-AL-PE (ASTM D1335) 


150 psig 



10.15.9 Drip Pans 

10.15.9.1 Where Required 

Where water heaters or hot water storage tanks are installed in locations where leakage will cause 
damage to the building structure, the tank or water heater shall be installed in a drip pan in accordance 
with Section 10.1 5. 9.b. 

10.15.9.2 Construction 

a. Drip pans shall be watertight and constructed of corrosion-resistant materials. Metallic pans shall 
be 24 gage minimum. Non-metallic pans shall be .0625-inch minimum thickness. Pans shall be not less 
than l-'/ 2 " deep and shall be of sufficient size to hold the heater without interfering with drain valves, 
burners, controls, and any required access. 



244 



2006 National Standard Plumbing Code-Illustrated 



b. High impact plastic pans shall be permitted under gas-fired water heaters where the heater is 
listed for zero clearance for combustible floors and the application is recommended by the pan manu- 
facturer. 

10.15.9.3 Drainage 

a. Drip pans shall have drain outlets not less than 3 / 4 " size, with indirect drain pipes extending to an 
approved point of discharge, a suitably located indirect waste receptor, or floor drain, or extend to 
within 2 to 6 inches above the adjacent floor. 

b. Discharge from a relief valve into a water heater pan shall be prohibited. 

10.15.10 Water Heaters Used for Space Heating 

a. Water heaters used for space heating shall be listed for such use. 

b. Piping and components connected to a water heater for space heating application shall be suitable for 
use with potable water. 

c. Where required, a water temperature control valve shall be installed in every combination water heating 
space heating system application to limit domestic hot water temperature to 140°F. The temperature control 
device shall be an ASSE 1017 listed device. 

10.16 SAFETY DEVICES FOR PRESSURE VESSELS 

10.16.1 Tank Protection 

a. Pressure vessels used for heating water or storing wateratpressures above atmosphericshall be 
protected by approved safety devices in accordance with one of the following methods: 

1 . A separate pressure relief valve and a separate temperature relief valve; or 

2. A combination pressure and temperature relief valve; or 

3. Either "a" or "b" above and an energy cut-off device. 

4. Tank construction conforming to a standard that does not require a temperature or pressure safety or 
reliefvalve. 

10.16.2 Pressure Relief Valves 

a. Pressure relief valves shall comply with the applicable codes, standards, and ratings of ASME ANSI 
andAGA. 

b. The valves shall have a relief rating adequate to meet the pressure conditions in the equipment served, 
and shall be installed either directly in a top tank tapping or in the hot or cold water piping close to the tank. 

c. There shall be no shutoff valve between the pressure reliefvalve and the tank. 

d. The pressure reliefvalve shall be set to open at not less than 25 p.s.i. above the street main pressure or 
not less than 25 p.s.i. above the setting of any house water pressure regulating valve. 

e. The setting pressure reliefvalve shall not exceed the rated working pressure of the tank being protected 
See Figure 10.16.6 



Comment: If a separate pressure reliefvalve is installed on a water heater storage tank, there must be no 
shutoff valves between it and the pressure tank. Also, there must be no shutoff valve in its discharge line 



2006 National Standard Plumbing Code-Illustrated 245 



WATER HEATER 
SHUT OFF VALVE 



PRESSURE 
RELIEF VAVLE 




HWf- 



NOTE 2 - 



-fCW 



■ WATER HEATER 
• SHUT OFF VALVE 



TEMPERATURE 
RELIEF VAVLE 

NO THREADED END 

II 
AIR GAP 

II 
NOTES 1,5,6 

NOTE 7 , 



WATER 
HEATER 



It 



COMBINATION 
P & T VALVE 

II 

NO THREADED END 



• AIR GAP 



-NOTES 
1,5,6 



SEPARATE RELIEF VALVES 



A COMBINATION RELIEF VALVE 



NOTES: 

1 . Relief valves can discharge to the floor where permitted by the Authority Having Jurisdiction. 

2. A shutoff valve in the hot water supply is permitted. 

3. Shutoff valves must not isolate relief valves from the tank that they are protecting. 

4. Threads are prohibited on the ends of relief valve discharge pipes to prevent the installation of a pipe 
cap if the valve begins to leak. 

5. Drains or indirect waste pipes that receive the discharge from relief valves must be sized according 
to Table 10.16.6, based on the size of the relief valve discharge pipe. 

6. The inlet to indirect waste piping must be elevated to establish sufficient static head above the 
horizontal portion of the drain to prevent spillage. 

7. Where two indirect waste pipes from relief valves are joined, the cross-sectional area of the common 
drain must be equal to or larger than the sum of the areas of the individual waste pipes. Refer to 
Section 9.3.6.b. 

Figure 10.16.6 
WATER HEATER RELIEF VALVES AND DISCHARGE PIPING 

10.16.3 Temperature Relief Valves 

a. Temperature relief valves shall be of adequate relief rating, expressed in BTU/HR, for the equipment 
served. 

b. The valves shall be installed so that the temperature sensing element is immersed in the hottest water 
within the top 6 inches of the tank. 

c. The valves shall be set to open when the stored water temperature reaches a maximum of 210°F. (See 
Section 3.3. 10.) 

d. The valves shall conform to an approved standard and shall be sized so that when the valve opens, the 
water temperature cannot exceed 210°F with the water heating equipment operating at maximum input. 
See Figure 10.16.6 

10.16.4 Combination Pressure-Temperature Relief Valves 

Combination pressure-temperature relief valves shall comply with all the requirements of the separate pres- 
sure and temperature relief valves. (See Section 3.3.10.) See Sections 10.16.2 and 10.16.3 



246 



2006 National Standard Plumbing Code-Illustrated 



10.16.5 Tankless Water Heaters 

a. Tankless instantaneous water heaters shall have a safety thermal cutout to shutoff the unit in the event of 
unsafe high temperature. The pressure and temperature tank protection required by Section 10.16.1 shall not be 
necessary unless required by the manufacturer's installation instructions. 

b. The outlet temperature control device for tankless water heaters shall be set to supply no more than 140°F 
hot water. 

10.16.6 Relief Valve Discharge Piping 

a. Piping from the outlet of a relief valve to the point of disposal shall be of a material suitable for potable 
water (see Section 3.4). Discharge pipes from temperature relief valves and combination pressure-tempera- 
ture relief valves shall be listed in Table 3.4 for hot water distribution, and shall be suitable for conveying 
water at 210°F to an open discharge. The pressure rating of the pipe at 210 deg F is not required to equal or 
exceed the pressure setting of the relief valve. 

b. There shall be no shut-off valve, check valve or other restricting device between a relief valve and the 
pressure vessel or piping system being protected. 

c. The discharge pipe shall be no smaller than the outlet size of its relief valve and shall extend to a point of 
disposal without valves, traps or rises that would prevent the relief valve from draining by gravity. Discharge 
end of the pipe shall not be threaded. 

d. An air gap shall be provided where relief valves discharge into an indirect waste pipe, floor drain, trench 
drain, service sink, mop basin, laundry sink, standpipe or other approved receptor. The minimum size of fixture 
drains or waste pipes that receive the discharge from relief valves shall be as indicated in Table 10. 16.6. 

e. Where relief valves discharge to the floor, the discharge pipe shall terminate not more than 6 inches nor 
less than 2 inches above the floor. 

f. If the point of disposal is outside the room or space in which the relief valve is located, an indirect gravity 
drain shall be provided from the room or space to the point of disposal. Indirect waste pipes shall be sized 
according to Table 10.16.6 and shall be of a material approved for potable water, sanitary drainage or storm 
drainage (see Tables 3.4, 3.5, and 3.7). A visible air gap shall be provided in the room or space in which the 
relief valve is located. 

EXCEPTION: Where water heaters are located above ceilings, the relief valve discharge pipe shall extend 
to a point of disposal or indirect waste that is readily observable in an area below the heater. 

g. Where two or more relief valves serving independent systems are located in the same area, each shall 
be discharged separately. Where such relief valves for independent systems are discharged into a common 
gravity drain or indirect waste pipe, the drain or waste pipe shall be sized according to the largest discharge 
pipe served. 

See Figure 10.16.6 



Table 10.16.6 
SIZE OF DRAINS OR WASTE PIPES RECEIVING RELIEF VALVE DISCHARGE 



Minimum Drain or 
Discharge Pipe Size Indirect Waste Size 



3/4" 2"* 

1" 3" 

1-1/2" 4 " 

2" 4" 

2-1/2" 6 » 



♦EXCEPTION: A laundry sink with 1-1/2" waste pipe. 



2006 National Standard Plumbing Code-Illustrated 247 



10.16.7 Vacuum Relief Valves 

Where a hot water storage tank or an indirect water heater is located at an elevation above the fixture outlets 
in the hot water system, a vacuum relief valve shall be installed on the storage tank or heater. See Figure 
10.16.7 



WATER HEATER 
SHUT OFF VALVE 



VACUUM RELIEF VALVE 



"A 

i — 1>4- 






HW 



CW 



WATER | 

HEATER , 



CW 



H WTO FIXTURES 
BELOW 



"& 



COMBINATION 
P & T VALVE 



DIP TUBE 



6" A.F.F. 



WATER HEATER 
SHUT OFF VALVE - 



S 



y 



VACUUM RELIEF VALVE 



v 






CW 



HW 



"% 



WATER 
HEATER 



CW 
i_ > 



COMBINATION 
P & T VALVE 



6" A.F.F. 



HW TO FIXTURES 
BELOW 



TOP FEED HEATER 



BOTTOM FEED HEATER 



NOTES: 

1 . Vacuum relief valves at water heaters prevent vacuum conditions that could siphon water from a 
tank, causing it to be damaged from dry firing or collapse. 

2. Vacuum relief valves are tested and rated under ANSI Z21 .22 - Relief Valves for Hot Water Supply 
Systems. 

3. Backflow prevention vacuum breakers are not intended for use as vacuum relief valves. 

4. Vacuum relief valves must be mounted higher than the tank being protected. 

Figure 10.16.7 
VACUUM RELIEF VALVES ON OVERHEAD WATER HEATER TANKS 

10.16.8 Replacement of Relief Valves 

a. Relief valves shall be maintained in proper working order and shall be replaced when necessary. 

b. Whenever a water heater is replaced, its temperature relief valve and pressure relief valve, or combina- 
tion temperature-pressure relief valve shall also be replaced and shall not be reused. 



248 



2006 National Standard Plumbing Code-Illustrated 



10.17 MANIFOLD-TYPE PARALLEL WATER DISTRIBUTION SYSTEMS 

10.17.1 General 

a. Parallel water distribution systems shall provide individual hot and cold water lines from a manifold to 
each fixture served. 

b. Manifolds shall be specifically designed and manufactured for parallel water distribution. 

c. Manufacturer's of such systems shall provide complete sizing and installation instructions, including any 
limitations or restrictions on use. 

d. Piping materials shall include coiled plastic or copper tube approved for hot and cold water distribution. 

10.17.2 Sizing 

See Appendix B for sizing manifolds and distribution lines. Distribution line sizes shall be as recommended by 
the system manufacturer to provide the fixture water flow rates listed in Section 10. 14.2a. The minimum line 
size shall be 3/8" nominal. 

10.17.3 Valving 

a. Each manifold outlet shall be equipped with a shut-off valve that identifies the fixture being supplied. 
Additional shut-off or stop valves at the fixtures shall be provided as required per Section 10. 12.4. 
EXCEPTION: Additional shut-off or stop valves at the fixtures shall not be required if the manifold is located 
within the same room or adjacent closet as the fixtures. 

b. Manifolds shall be readily accessible. 

10.17.4 Support 

a. Tube bundles for manifold systems shall be supported in accordance with Chapter 8 of this Code. 

b. Supports at changes in direction shall be in accordance with the manufacturer's recommendations. 

10.18 DRINKING WATER TREATMENT UNITS 

10.18.1 Compliance with Standards 

Drinking water treatment units shall comply with the standards listed in Table 3. 1 .3. 

10.18.2 Air Gap Discharge 

Discharge from all drinking water treatment units shall be installed with an air gap. 

EXCEPTION: Reject water connections from reverse osmosis drinking water treatment units shall be 

through an air gap or alternate air gap device in accordance with the requirements of NSF 58. 

10.18.3 Connection Tubing 

The tubing to and from the drinking water treatment unit shall be of a size and material as recommended by 
the manufacturer. The tubing shall comply with NSF 14, NSF 58 or NSF 61. 

10.19 SIZING OF RESIDENTIAL WATER SOFTENERS 

Residential-use water softeners shall be sized per Table 10.19. 



2006 National Standard Plumbing Code-Illustrated 249 



TABLE 10.19 
SIZING OF RESIDENTIAL SOFTENERS 



i 

Required Size of Softener Connection (in.) Number of Bathroom Groups Served 

3/4 Up to 2 2 



Up to 4 3 



' Installation with a kitchen sink and dishwasher, laundry tray and automatic clothes washer. 

2 An additional water closet and lavatory shall be permitted without an increase in sizing. 

3 Over four Bathroom Groups, the softener shall be engineered for the specific installation. 



■"" 2006 National Standard Plumbing Code-Illustrated 



HWBMMM — M 

wBmmm 



m 



jBNI 




Sanitary Drainage Systems 

11.1 MATERIALS 

See Section 3.1. 

11.2 BUILDING SEWERS 

11.2.1 Sewer or Drain in Filled Ground 

Building sewers or building drains that are installed in filled or unstable ground shall be installed in accordance 
with Section 2.6. 

1 1.2.2 Existing Building Sewers and Drains 

Existing building sewers and drains may be used in connection with new building sewer and drainage systems 
only when found by examination to conform to the new system in quality of material prescribed by this Code. 

11.2.3 Building Sewer and Building Drain Size 

The size of the building sewer and the size of the building drain shall be determined by fixture unit loads 
connected in accordance with Table 11. 5.1 A. See Figures 11.5.1 - A and - B 

11.3 DRAINAGE PIPING INSTALLATION 

1 1 .3.1 Slope of Horizontal Drainage Piping 

a. Horizontal drainage piping shall be installed in uniform alignment at uniform slopes not less than 1/4 inch 
per foot for 2-inch size and smaller, and not less than 1/8 inch per foot for 3-inch size and larger. 

b. Where conditions do not permit building drains and sewers to be laid with slope as great as that specified 
a lesser slope may be permitted by the Authority Having Jurisdiction. See Appendix K for the approxi- 
mate discharge rates and flow velocities in drains at various slopes. 

11.4 FIXTURE UNITS 

11.4.1 Load on Drainage Piping 

The load on drainage system piping shall be computed in terms of drainage fixture unit values in accordance 
with Table 1 1 .4. 1 and Section 1 1 .4.2. 

1 1.4.2 Conversion of Flow in GPM to DFU 

Where the discharge rate of fixtures or equipment is expressed in gallons per minute (GPM), two (2) drainage 
fixture units (DFU) shall be allowed for each gallon per minute (GPM) of flow. 



2006 National Standard Plumbing Code-Illustrated ~-, 



Table 11.4.1 
DRAINAGE FIXTURE UNIT (DFU) VALUES 


HEAVY-USE ASSEMBLY 


TYPE OF FIXTURES OTHER THAN DWELLING UNITS 




SERVING 3 OR MORE DWELLING UNITS 




INDIVIDUAL DWELLING UNITS 




S V? IIROOM GROUPS j I W INt, 1.6 GPF 
GK A\ 1 1 Y-TANKWA TEK CLOSETS 










Half-bath or Powder Room 


3.0 


2.0 






1 Bathroom Group 


5.0 


3.0 






1 V 2 Bathrooms 


6.0 








2 Bathrooms 


7 








2 V 2 Bathrooms 


8.0 








3 Bathrooms 


9.0 








Each Additional 7 2 Bath 


0.5 








Each Additional Bathroom Group 


1.0 








BATIIRJ >0,V1GR0(;PS HAYING 1.6 GI'E 
PRESSURE '1 ANKW VI EUC'i OSE IS 










Half-bath or Powder Room 


3.5 


2 5 






1 Bathroom Group 


5.5 


3.5 






1 V 2 Bathrooms 


6.5 








2 Bathrooms 


7.5 








2 V 2 Bathrooms 


8.5 








3 Bathrooms 


9.5 








Each Additional V 2 Bath 


0.5 








Each Additional Bathroom Group 


1.0 








BATHROOM GROUPS HA\ INC 3.5 GPF 
TANK-TYPE \VATER( LOSETS 










Half-bath or Powder Room 


3.0 


2.0 






1 Bathroom Group 


6.0 


4.0 






1 'A Bathrooms 


8.0 








2 Bathrooms 


10.0 








2 V 2 Bathrooms 


11.0 








3 Bathrooms 


12.0 








Each Additional 7 2 Bath 


0.5 








Each Additional Bathroom Group 


1.0 








BATH GROUP (1.6 GPF Flushometer Valve) 


5.0 


3.0 






BATH GROUP (3.5 GPF Flushometer Valve) 


6.0 1 4.0 







252 



2006 National Standard Plumbing Code-Illustrated 



Table 11.4.1 (Continued) 
DRAINAGE FIXTURE UNIT (DFU) VALUES 


HEAVY-USE ASSEMBLY 


TYPE OF FIXTURES OTHER THAN DWELLING UNITS 




SERVING 3 OR MORE DWELLING UNITS 




INDIVIDUAL DWELLING UNITS 




INDIVIDUAL 1-LYH.RKS 










Bathtub or Combination Bath/Shower, 1 '/i" Trap 


2 


2.0 






Bidet, l'/V Trap 


1.0 


1.0 






Clothes Washer, Domestic, 2" Standpipe 


3.0 


3.0 


3.0 




Dishwasher, Domestic, with Independent Drain 


2.0 


2.0 


2.0 




Drinking Fountain or Watercooler 






0.5 




Food- Waste-Grinder, Commercial, 2" Min Trap 






3.0 




Floor Drain, Auxiliary 






0.0 




Kitchen Sink, Domestic, with One 1 'h" Trap 


2.0 


2.0 


2.0 




Kitchen Sink, Domestic, with Food- Waste-Grinder 


2.0 


2.0 


2.0 




Kitchen Sink, Domestic, with Dishwasher 


3.0 


3.0 


3.0 




Kitchen Sink, Domestic, with Grinder and Dishwasher 


3.0 


3.0 


3.0 




Laundry Sink, One or Two Compartments, 1 ] k" Waste 


2.0 


2.0 


2.0 




Laundry Sink, with Discharge from Clothes Washer 


2.0 


2.0 


2.0 




Lavatory, 1 Vi" Waste 


1.0 


1.0 


1.0 


1.0 


Mop Basin, 3" Trap 






3.0 




Service Sink, 3" Trap 






3.0 




Shower Stall, 2" Trap 


2.0 


2.0 


2.0 




Showers, Group, per Head (Continuous Use) 






5.0 




Sink, 1 'h" Trap 


2.0 


2.0 


2.0 




Sink, 2" Trap 


3.0 


3.0 


3.0 




Sink, 3" Trap 






5.0 




Trap Size, 1 "A" (Other) 


1.0 


1.0 


1.0 




Trap Size, 1 <h" (Other) 


2.0 


2.0 


2.0 




Trap Size, 2" (Other) 


3.0 


Ml 


3.0 




Trap Size, 3" (Other) 






5.0 




Trap Size, 4" (Other) 






6.0 




Urinal, 1 .0 GPF 






4.0 


5.0 


Urinal, Greater Than 1.0 GPF 






5.0 


6.0 


Wash Fountain, 1 V2" Trap 






2.0 




Wash Fountain, 2" Trap 






3.0 




Wash Sink, Each Set of Faucets 






2.0 





2006 National Standard Plumbing Code-Illustrated 



253 



Table 11.4.1 (Continued) 
DRAINAGE FIXTURE UNIT (DFU) VALUES 


f HEAVY-USE ASSEMBLY 


TYPE OF FIXTURES OTHER THAN DWELLING UNITS 




SERVING 3 OR MORE DWELLING UNITS 




INDIVIDUAL DWELLING UNITS 






llHISi 


lilillll 




iijilill 


Water Closet, 1 .6 GPF Gravity or Pressure Tank 


3.0 


3.0 


4.0 


6.0 


Water Closet, 1 .6 GPF Flushometer Valve 


3.0 


3.0 


4.0 


6.0 


Water Closet, 3.5 GPF Gravity Tank 


4.0 


4.0 


6.0 


8.0 


Water Closet, 3.5 GPF Flushometer Valve 


4.0 


4.0 


6.0 


8.0 


Whirlpool Bath or Combination Bath/Shower, 1 V2" Trap 


2.0 


2.0 



NOTES: (Table 11.4.1): 

1. A Bathroom Group, for the purposes of this Table, consists of not more than one water closet, up to two lavatories, and either one 
bathtub, one bath/shower combination, or one shower stall. Other fixtures within the bathing facility shall be counted separately to 
determine the total drainage fixture unit load. 

2. A Half-Bath or Powder Room, for the purposes of this Table, consists of one water closet and one lavatory. 

3. For unlisted fixtures, refer to a listed fixture having a similar flow and frequency of use. 

4. When drainage fixture unit (DFU) values are added to determine the load on the drainage system or portions thereof, round the sum to the 
nearest whole number before referring to Tables 11. 5.1 A, 1 1.5. IB, or 12.16.6A for sizing the drainage and vent piping. Values of 0.5 or 
more should be rounded up to the next higher whole number (9.5 = 10 DFU). Values of 0.4 or less should be rounded down to the next 
lower whole number (9.4 = 9 DFU). 

5. "Other Than Dwelling Units" applies to business, commercial, industrial, and assembly occupancies other than those defined under 
"Heavy-Use Assembly." Included are the public and common areas in hotels, motels, and multi-dwelling buildings. 

6. "Heavy-Use Assembly" applies to toilet facilities in occupancies that place heavy, but intermittent, time-based loads on the drainage 
system, such as; schools, auditoriums, stadiums, race courses, transportation terminals, theaters, and similar occupancies where queuing is 
likely to occur during periods of peak use. 

7. Where other than water-supplied fixtures discharge into the drainage system, allow 2 DFU for each gallon per minute (gpm) of flow. (See 
Section 11.4.2.) 



11.4.3 Diversity Factors 

In certain structures such as hospitals, laboratory buildings, and other special use or occupancy buildings 
where the ratio of plumbing fixtures to occupants is proportionally more than required by building occupancy 
and in excess of 1 ,000 fixture units, the Authority Having Jurisdiction may permit the use of a diversity factor 
for sizing branches, stacks and building sewers. 



Comment: The Authority Having Jurisdiction may permit the use of a diversity factor in systems where 
the number of fixtures per person is higher than normal. A hospital is such an example where toilet 
facilities are provided in each patient room for the convenience of the patients. The load on the drain- 
age system is created by the number of persons served, not by the number of plumbing fixtures that are 
installed. 



254 



2006 National Standard Plumbing Code-Illustrated 



11.5 DETERMINING DRAINAGE PIPE SIZES 

11.5.1 Selecting the Size of Drainage Piping 

Pipe sizes shall be determined from Table 1 1.5. 1A and 1 1.5. IB on the basis of the drainage fixture unit load 
(DFU) computed from Table 11.4.1 and Section 11.4.1. Sanitary drainage pipe sizes shall not be reduced in 
the direction of flow. 

EXCEPTION: Drain pipe sizes for individual fixtures shall be not less than the minimum trap size required in 
Section 5.2. See Figures 11.5.1 - A and - B 







Table 11.5.1 A 












BUILDING DRAINS AND SEWERS 1 








Maximum Number of Drainag< 


J Fixture Units (DFU) 


That May 


Be 






Connected to Any Portion of the Building Drain or the 


Building Sewer. 




Pipe Size- 






Slope Per Foot 








Inches 


1/16-Inch 


1/8-Inch 


1/4-Inch 




1/2-Inch 




2 






21 




26 




3 






42 2 




50 2 




4 




180 


216 




250 




5 




390 


480 




575 




6 




700 


840 




1,000 




8 


1,400 


1,600 


1,920 




2,300 




10 


2,500 


2,900 


3,500 




4,200 




12 


3,900 


4,600 


5,600 




6.700 




15 


7,000 


8,300 


10,000 




12,000 





1 . On-site sewers that serve more than one building may be sized according to the current standards and specifications 
of the Authority Having Jurisdiction for the public sewers. 

2. See Sections 11.5.6.d, 11.5.6.e, and 11.5.6.f. 









Table 11.5.1B 






HORIZONTAL 


FIXTURE BRANCHES AND STACKS 




Maximum Number of 


Drainage Fixture Units 


(DFU) That May Be Connected To: 










Stacks 


with More Than Three 




Any 


One Stack of 
Three Branch 






Branch Intervals 








Pipe Size 


Horizontal 


Intervals or 






Total at One 


Inches 


Fixture Branch 1 


Less 


Total 


for Stack 


Branch Intervals 


VU 


1 


1 




1 


1 


Vh 


3 


4 




8 


2 


2 


6 


10 




24 


6 


3 


20 2 


48-' 




72 3 


20 3 


4 


160 


240 




500 


90 


5 


360 


540 




1,100 


200 


6 


620 


960 




1,900 


350 


8 


1,400 


2,200 




3,600 


600 


10 


2,500 


3,800 




5,600 


1,000 


12 


3,900 


6,000 




8,400 


1,500 


15 


7,000 











1 . Does not include branches of the building drain. 

2. See Section 11.5.6.b. 

3. See Section 11.5.6.C. 



2006' National Standard Plumbing Code-Illustrated 255 



EXAMPLE OF SIZING DRAINAGE PIPING 
(Refer to Figures 11. 5.1 -A and -B) 

1. To size the drainage system, start at the top floor and work down to the building drain. 

2. Draw a diagram of the system showing the various fixtures. 

3. Assign a drainage fixture unit (DFU) value to each fixture or fixture group using Table 11.4.1. Where a 
specific fixture type is not listed, use the "Sink" or "Trap Size" values. 

4. Size the horizontal fixture branches on each floor using the pipe sizes in Table 11.5.1.B for the number of 
DFUs listed in the second column. 

5. Size the stacks using the pipe size in Table 11. 5.1. B for the number of DFUs listed in columns 3,4, or 5, 
depending on the number of branch intervals. Check the limits on DFUs in any one branch interval and 
the total for the stack. Size the stack accordingly. 

6. For Stack A in Figure 11.5.1-B, each horizontal branch drain has 90 DFU and is 4" size. The stack is 
4" size from top to bottom. 

7. For Stack B in Figure 11.5.1-B, the horizontal branch drains are all 4" size. Although the total number 
of DFUs is the same as Stack A (450 DFU), the lowest branch interval has more than 90 DFU and must 
be 5" size. The stack cannot be smaller than any of its branches and thus must be 5" size at the base. 
The upper portions of the stack can be 4 " size. 

8. For Stack C in Figure 11.5.1-B, although the total number of DFUs is less than Stack A and Stack B, the 
top horizontal branch drain must be 5" size because it has 200 DFUs. The entire stack must 5" size, 
even though 4" would have been adequate for the total number of DFUs. 

9. Stack D in Figure 11.5.1-B only has three branch intervals and can be sized using column 3 in Table 
11.5.1.B. Each of the 3" horizontal fixture branches is limited to four 1.6 GPF water closets per Section 
11.5.6.b. Each branch interval of the 3" stack is limited to four 1.6 GPF water closets and the entire 3" 
stack is limited to twelve 1.6 GPF water closets per Section 11.5.6.C If the number of water closets on 
any branch or the stack exceed the limits for 3 " pipe, the branch and downstream stack must be in- 
creased to 4" size. 

10. In Figure 11.5.1-A, Stack A is 4" size with 450 DFUs. In Table 11.5.1.A, Branch A of the building drain 
must be 5" size sloped 1/4" per foot. If 1/4" slope cannot be maintained, the branch must be increased to 
6" size sloped 1/8" per foot. 

11. In Figure 11.5.1-A, Stack B is 5" size with 450 DFUs. In Table 11.5.1.A, Branch B of the building drain 
can remain 5" size if sloped 1/4" per foot. Otherwise, the size must be increased if run at less slope. 

12. In Figure 11.5.1-A, Section B-C of the building drain is 450 + 450 = 900 DFUs. In Table 11.5.1.A, it 
needs to be 8" size, but the slope can be reduced to 1/8" per foot. 

13. In Figure 11.5.1-A, Stack C is 5" size with 404 DFUs. In Table 11. 5. LA, Branch C can remain 5" size, 
but must be sloped at 1/4" per foot. Otherwise, the size must be increased if run at less slope. 

14. In Figure 11.5.1-A, Section C-D of the building drain is 900 + 404 = 1304 DFUs. Section C-D of the 
building drain must be at least 8" size because Section B-C is 8" size. In Table 11.5.1.A, 8" size is 
adequate at 1/8" or 1/16" per foot slope. Section 11.3.1 requires 1/8" slope for pipe 4" and larger. 
However, Table K-l indicates that the velocity in Section C-D when flowing 1/2 full at 1/16" slope is not 
less than the 2 feet per second minimum and the reduced slope might be approved by the Authority 
Having Jurisdiction. 

15. In Figure 11.5.1-A, Stack D is 3" size with 48 DFUs. In Table 11. 5. LA, branch D of the building drain 
could remain 3" if sloped 1/2" per foot. However, Section 11.5.6a limits it to four 1.6 GPF water closets. 
Otherwise, it would have to be increased to 4" size. 

16. In Figure 11.5.1-A, Section D-E of the building drain is 1304 + 48 = 1352 DFUs. Section D-E must be 
at least 8" size because Section C-D is 8" size. In Table 11.5.1.A, 8" size is still adequate for 1352 
DFUs. 

1 7. In Figure 11.5.1-A, horizontal fixture branch E is 4 + 1+4 + 1= 10 DFUs. In Table 11.5.1.B, the 
branch needs to be 3" size. It has less than the allowable number of water closets in Section 11.5.6.b. 

18. In Figure 11.5.1-A, the load on the last section of the building drain and the building sewer is 1352 + 10 
= 1362 DFUs. The 8" size of Section D-E is still adequate for the final section of the building drain and 
for the building sewer. 



256 



2006 National Standard Plumbing Code-Illustrated 




BUILDING DRAIN 
BRANCH A 



BUILDING DRAIN(B-C) 



BUILDING SEWER 



HORIZONTAL 
FIXTURE BRANCH E 



Figure 11.5.1 - A 
SIZING BUILDING DRAINS AND SEWERS 



2006 National Standard Plumbing Code-Illustrated 



257 



CK "A" 


STACK "B" 

I 
I 


STACK "C" 

I 
| 


STACK "D" 

I 

I 


4" - 90 DFU 


I 
I 
I 4" - 90 DFU 


I 

I 5" - 200 DFU 


I 


3" - 20 DFU 


/ — 




/ 


f— 


/ 


— 90 DFU -4" 




— — 90 DFU -4" 




— 200 DFU - 5" 






4" -90 DFU 




4" - 90 DFU 




4" - 90 DFU 

/ 




— — 20 DFU -3" 


/ 




— 180 DFU -4" 




-« — 180 DFU -4" 




— 290 DFU - 5" 






4"- 90 DFU 




4" - 85 DFU 

/ 




3" -18 DFU 

/ 




3" - 8 DFU 


/ 


— 270 DFU -4" 




— 265 DFU -4" 




— 308 DFU - 5" 




— 28 DFU -3" 


4" - 90 DFU 

/ 




4" - 85 DFU 

/ 




2" - 6 DFU 

/ 




3" - 20 DFU 

/ 


——360 DFU -4" 




— — 350 DFU -4" 




— — 314 DFU - 5" 




4" - 90 DFU 

/ 




5" -100 DFU 

/ 




4" - 90 DFU 




——48 DFU -3" 


— —450 DFU- 4" 




-•—450 DFU -5" 




— — 404 DFU - 5" 







TOTAL -450 DFU TOTAL -450 DFU TOTAL -404 DFU TOTAL- 48 FDU 



Figure 11.5.1 - B 
SIZING DRAINAGE STACKS 



258 



2006 National Standard Plumbing Code-Illustrated 



11.5.2 Minimum Size of Soil and Waste Stacks 

Soil and waste stacks shall be sized according to Table 1 1.5. IB. based on the number of branch intervals and 

drainage fixture unit load. 

EXCEPTION: Sections of stacks shall not be smaller than their largest branch connection, except that stack 

sizes shall not be reduced in the direction of flow. 

See Figure 11.5.2 



T 



4" BUILDING DRAIN (NOTE 4) 
f 



STACK VENT (NOTE 5) 



r 



30 D.F.U. 4" HORIZONTAL 
FIXTURE BRANCH (NOTE 2) 



4" SOIL OR WASTE STACK (NOTE 3) 



NOTES: 

1 . The figure shows a sanitary drainage piping system with one branch interval. 

2. The horizontal branch drain with 30 DFU must be 4" minimum size per Table 1 1 .5.1 B. 

3. The stack size must be 4" minimum size, even though Table 1 1 .5.1 B indicates that a 3" stack with 
one branch interval could handle 48 DFU. 

4. The building drain must be 4" minimum size, even though Table 1 1 .5.1 A indicates that a 3" building 
drain could handle 42 DFU at 1/4" slope. 

5. The stack vent must be 2" minimum size, which is 1/2 the size of the 4" drainage stack. 

Figure 11.5.2 
MINIMUM SANITARY DRAINAGE PIPE SIZES 



1 1.5.3 Horizontal Fixture Branches and Branches of the Building Drain: 

Horizontal fixture branches shall be sized according to Table 1 1 .5. IB to the point where they connect to the 
building drain or a branch of the building drain. Building drain piping that serves two or more horizontal fixture 
branches are branches of the building drain and may be sized according to Table 1 1.5.1 A. 

11.5.4 Provision for Future Fixtures 

When provision is made for the future installation of fixtures, those provided for shall be considered in deter- 
mining the required sizes of drain and vent pipes. Construction to provide for such future installation shall be 
terminated with a plugged fitting or fittings. See Figure 11.5.4 



2006 National Standard Plumbing Code-Illustrated 



259 



Comment: Drainage or vent piping installed with plugged or capped fittings for the connection of future 
fixtures does not constitute a dead end. Such piping should be accessible. 



PIPING SIZED FOR 
FUTURE FIXTURE 




If 



"\ 



J. 




=m= 



PLUGGED OR CAPPED 
CONNECTIONS FOR 
FUTURE FIXTURE 



WASTE 



Figure 11.5.4 
DRAIN AND VENT PROVISIONS FOR FUTURE FIXTURES 

1 1 .5.5 Minimum Size of Underground Drainage Piping 

No portion of the drainage system installed underground shall be less than two inch pipe size. 
EXCEPTION: Condensate waste, tub and shower traps and trap arms, and piping that receives the discharge 
from relief valves after an air gap. 

11.5.6 Restrictions on the Number of Water Closets on 3" Drains 

a. 3" Horizontal Fixture Branches 

No more than four water closets or bathroom groups shall be installed on a 3" horizontal fixture branch. 
EXCEPTION: Where the water closets are rated 3.5 gallons or more per flush, no more than two water closets 
or bathroom groups shall be permitted. 

b. 3" Stacks 

No more than four water closets or bathroom groups shall be installed within any branch interval of a 3 " stack, 
and no more than a total of twelve on the stack. 

EXCEPTION: Where the water closets are rated 3.5 gallons or more per flush, no more than two water closets 
or bathroom groups shall be permitted in any branch interval, and no more than a total of six on the stack. 

c. 3" Building Drains and Sewers 

1 . In single dwelling units, no more than six water closets or bathroom groups shall be installed on a 3" 
building drain or building sewer, or branches thereof. 

EXCEPTION: Where the water closets are rated 3.5 gallons or more per flush, no more than three water 
closets or bathroom groups shall be permitted. 

2. In other than single dwelling units, no more than four water closets or bathroom groups shall be 
installed on a 3 " building drain or building sewer, or branches thereof. 

EXCEPTION: Where the water closets are rated 3.5 gallons or more per flush, no more than two water closets 
or bathroom groups shall be permitted. 

d. Mixed Water Closets on 3" Drains 

Where 3" drainage piping serves a mixture of 1 .6 GPF water closets and 3.5 (or higher) GPF water closets, 
the 3.5 (or higher) GPF water closets shall be counted as two water closets for the purpose of determining the 
total number of water closets on the 3" drainage piping. The drainage fixture unit (DFU) load for each 3.5 (or 
higher) GPF water closet shall be as indicated in Table 1 1.4.1 



260 



2006 National Standard Plumbing Code-Illustrated 



11.5.7 Stack Size Reduction 

a. Stacks shall be sized according to the total accumulated drainage fixture unit load (DFU) at each story or 
branch interval. 

b. The stack size shall be permitted to be reduced as the DFU load decreases on the upper portion of the 
stack. 

EXCEPTION: No portion of a stack shall be less than one-half of the required size at the base of the 
stack. 



11.6 SIZING OF OFFSETS IN DRAINAGE PIPING 



11.6.1 Vertical Offsets 

An offset in a stack that is 45 degrees or more from horizontal shall be sized as a straight vertical stack in 
accordance with Table 1 1.5. IB. See Figure 11.6.1 



FROM UPPER FLOORS 



NOTE 2 



OFFSET OF 45° OR MORE FROM 
HORIZONTAL CAN BE SIZED AS A 
STRAIGHT VERTICAL STACK 




NOTE 2 



7THFLR 



^ TO LOWER FLOORS 
NOTES: 

1. Vertical offsets in drainage stacks do not affect the stack size. 

2. If a drain stack with ten or more branch intervals above a vertical offset has fixtures or horizontal 
branches connected within two feet above or below the offset, a relief vent must be provided for the 
lower portion of the stack. 



Figure 11.6.1 
VERTICAL OFFSETS IN DRAINAGE STACKS 

11.6.2 Reserved 

11.6.3 Offsets Above the Highest Branch 

An offset in a stack above the highest horizontal branch drain connection shall not affect the size of the 
stack, only the developed length of the stack vent. See Figure 11.6.3 



2006 National Standard Plumbing Code-Illustrated 



261 



I 

r 



I. V.T.R. 



HIGHEST 
FIXTURE lr- 
BRANCH 



■N 



FIXTURE 

BRANCH 



r 



nJ 



STACK TO LOWER FLOOR 



NOTES: 

1 . The offset does not affect the size of the stack, only its developed length. 

Figure 11.6.3 
OFFSETS IN STACKS ABOVE THE HIGHEST BRANCH DRAIN CONNECTION 



11.6.4 Reserved 

11.6.5 Horizontal Offsets 

a. A stack with an offset of less than 45 degrees from the horizontal shall be sized as follows: 
1 : The portion of the stack above the offset shall be sized as a regular stack based on the total number of 
fixture units above the offset. 

2. The offset shall be sized as a uilding drain (See Table 1 1 .5.1 A). 

3. The portion of the stack below the offset shall be sized as the offset or based on the total number of 
fixture units on the entire stack, whichever is the larger. 

4. A relief vent shall be provided for the offset is required by Section 12.3.3. 
See Figure 11.6.5 



262 



2006 National Standard Plumbing Code-Illustrated 



VENT STACK 



3 FEET MIN f 



ALTERNATE 

YOKE VENT 

(NOTE 7) 



NOTE 6 



U-® 



A 



X 



I — dff.<;pt ^~s 



-OFFSET 



NOTES: 

1 . A horizontal offset is one that is less than 45 degrees from horizontal. 

2. Vents for the branch drains and required cleanouts are not shown in the Figure. 

3. The upper portion of the stack (A-B) is sized based on either the total number of drainage fixture 
units (DFU) in each branch interval or the total accumulated load on the upper portion of the stack 
per Table 1 1 .5.1 .B. The stack size can be reduced as it rises, up to 1/2 size in accordance with 
Section 11.5.7. 

4. The horizontal offset (B-C) must be sized as a building drain per Table 1 1 .5. 1 .A, based on the total 
drainage fixture units (DFU) above the offset. 

5. The lower portion of the stack (C-D) cannot be smaller than the size of the horizontal offset The 
lower portion must be sized based on either the size of the horizontal offset, the total drainage 
fixture units (DFU) in each branch interval of the lower portion, or the total accumulated load on the 
upper and lower portions of the stack per Table 1 1 .5.1 .B, whichever is larger. The stack size can be 
reduced as it rises, up to 1/2 size in accordance with Section 1 1 .5.7. 

The stack offset must be vented The upper and lower portions of the stack can be vented sepa- 
rately in accordance with Section 12.3.3.a. 

An alternate vent for the lower portion of the stack can be a yoke vent below the offset that connects 
to the vent stack at least 3 feet above the offset. The 3 foot elevation reduces the possibility of 
spillover from the drain stack into the vent stack. 



6. 



7. 



Figure 11.6.5 
HORIZONTAL OFFSETS IN STACKS 



2006 National Standard Plumbing Code-Illustrated 



263 



11.7 SUMPS AND EJECTORS 



11.7.1 Building Subdrains 

a. Building sanitary drains that cannot be discharged by gravity shall be discharged into a sump pit from 
which the contents shall be lifted and discharged into the building gravity drainage system by automatic 
pumping equipment or by an equally efficient method approved by tire Authority Having Jurisdiction. 

b. Only drains that must be lifted for gravity discharge shall be connected to such sump pits. All other 
drains shall discharge by gravity. 

EXCEPTION: Existing buildings. 

c. Sump pits shall be a minimum of 1 5 inches in diameter and 1 8 inches deep, and be accessible, tightly 
covered, and vented. 

See Figure 11.7.1 



w.c. 



BATHTUB 



U 



LAV LAV 



"N 



w.c. 



J 



STACK CONNECTED TO GRAVITY DRAIN 
EVEN THOUGH IT MAY BE MORE 
CONVENIENT TO CONNECT IT TO THE 
AUTOMATIC PUMP 



BUILDING DRAIN 



X 



FULL PORT 
SHUT OFF VALVE 

CHECK VALVE — 



A 



I 



SEALED COVER 



AUTOMATIC SEWAGE 
PUMP IN SUMP » 



VENT THRU ROOF OR 
COMBINE WITH OTHER 
VENTS, SIZE PER SECTION 
12.14 AND TABLE 12.14.2 



LAV 



VENT THRU ROOF OR 
COMBINE WITH OTHER 
VENTS 



W.C. 
_| 



BUILDING SUB-DRAIN 
BELOW SEWER 



NOTES: 

1 . Sewage pumps and ejectors must have audible, visual, or combination high level alarms per Section 

11.7.11. 

Figure 11.7.1 
A BUILDING SUBDRAIN AND SEWAGE PUMP 



11.7.2 Reserved 

11.7.3 Reserved 

11.7.4 Venting 

Building subdrain systems shall be vented according to Chapter 12 of this Code. 



264 



2006 National Standard Plumbing Code-Illustrated 



Comment: Sump pits with centrifugal sewage pumps must be vented in accordance with Section 12.14.2 
and Table 12.14.2. Pneumatic sewage ejectors must be separately vented according to Section 12.14.3. 



11.7.5 Reserved 

11.7.6 Grinder Pump Ejector 

a. Grinder pumps shall be permitted to be used when approved by the Authority Having Jurisdiction and 
installed according to the manufacturer ' s recommendations . 

b. The rated flow velocity for grinder pump discharge piping shall be not less than 2 feet per second. 

c. The size of grinder pump discharge piping shall be: 

1. 1-1/4" size for up to 25 gallons per minute. 
2.1-1/2" size for up to 35 gallons per minute. 
3. 2" size for up to 65 gallons per minute. 

11.7.7 Pneumatic Ejectors 

Vents from pneumatic ejectors shall be carried separately to the open air as a vent terminal in accordance 
with Section 12.14.2. 

11.7.8 Sewage Ejectors or Sewage Pumps 

a. A sewage ejector or sewage pump receiving the discharge from a water closet or urinal shall have a 
minimum capacity of 20 gallons per minute. 

b. The discharge piping from a sewage ejector and sewage pump shall include a backwater valve and a 
full-way shutoff valve. 

c. Ejectors or pumps in single dwelling units shall be capable of passing a 1-1/2 inch diameter solid 
EXCEPTION: Grinder pumps. 

d.In other than single dwelling units, ejectors and pumps shall be capable of passing a 2 inch diameter solid 
EXCEPTION: Grinder pumps. 

11.7.9 Individual Fixture Ejector or Pump 

a. Individual fixtures other than water closets, urinals, and similar fixtures, may discharge directly into an 
approved fixture-mounted ejector or pump, or into receptors having ejectors or pumps. 

b. The discharge piping from a sewage ejector or sewage pump for an individual fixture shall be sized on a 
hydraulic basis and include a backwater valve and full-way shutoff valve. 

c. Direct-mounted equipment may be manually or automatically operated. 

d. The installation of manually or automatically operated equipment shall not be subject to the venting 
requirements of this Code, but shall be vented only as required for proper operation of the equipment. 

e. A vent on the fixture side of the trap may terminate locally in the area served. 

f. If the equipment provides a proper water seal, additional traps are not required. 
See Figure 11.7.9 



2006 National Standard Plumbing Code-Illustrated 



265 




GRAVITY ■ 
DRAIN 



SIZE RECOMMENDED 
BY MANUFACTURER 



FULL WAY 
SHUTOFF VALVE 



CHECK VALVE 



VENT IF REQUIRED 
BY MANUFACTURER 




DIRECT MOUNTED 



FLOOR MOUNTED 



NOTES: 

1 . Individual fixture drain pumps should be installed in accordance with the manufacturer's instructions. 

2. Traps and vents should be installed when recommended by the pump manufacturer. 

3. Manufacturers generally require screens on the sink outlet and lint filters on washing machine 
discharges to prevent clogging the pump. 

Figure 11.7.9 
INDIVIDUAL FIXTURE DRAIN PUMPS 

11.7.10 Macerating Toilet Systems 

a. The sump for macerating toilets shall be vented with a 1-1/4" vent. 

b. The discharge line from the sump shall be not less than 3/4" size and include a check valve and full-way 
shut off valve. 

c. The distance from a macerating toilet system to a gravity drain shall not exceed the recommendations 
of the manufacturer of the macerating toilet system 

11.7.11 High Water Alarms 

All sewage ejector or sewage pump systems shall be provided with an audible, visual, or combination high 

water alarm device. 

EXCEPTION: Sewage ejectors and sewage pumps serving individual fixtures. 

11.8 RESERVED 

11.9 BRANCH CONNECTIONS NEAR THE BASE OF STACKS 

a. Horizontal branch drain connections shall not be made within 10 pipe diameters downstream from the base 
of a stack. 

b. A relief vent shall be provided for stacks of five or more branch intervals, either above the base of the stack 
or within 10 pipe diameters downstream from the base of the stack. 



266 



2006 National Standard Plumbing Code-Illustrated 



c. Branch drains shall not connect between the base of a stack and its relief vent. 
See Figures 11.9 and 12.3.1 



PO 




AIR 

LIQUID WASTE 

STACK 



HYDRAULIC JUMP 



J 



VARIES TO MAXIMUM 
10 X STACK DIAMETER 

NOTES: 

1 . Because of "hydraulic jump", stable flow does not occur in the horizontal drain until a distance of up 
to 1 times the pipe size "D" from the base of the stack. 

2. "Hydraulic jump" can completely close the horizontal drain. 

3. "Hydraulic jump" can occur in stacks sized for as few as 4 drainage fixture units (DFU). 

4. Branch drain connections are prohibited within 10 x "D" of the base of the stack where hydraulic 
jump can occur. 



Figure 11.9 
HYDRAULIC JUMP AT THE BASE OF DRAINAGE STACKS 

11.10 BRANCH CONNECTIONS TO OFFSETS IN STACKS 

a. Branch drains shall be permitted to connect to a horizontal stack offset, provided that the connection is not 
less than 10 pipe diameters downstream from the upper portion of the stack 

b. Where stacks have five or more branch intervals above a horizontal offset, there shall be no branch connec- 
tions to the stack within 2 feet above or below the offset. 

c. Where stacks having five or more branch intervals above a vertical offset have branch connections to the 
stack within 2 feet above or below the offset, the offset shall be vented as required for a horizontal offset. 

11.11 SUDS PRESSURE ZONES 



11.11.1 Genera] 

Where suds-producing fixtures on upper floors discharge into a soil or waste stack, suds pressure zones shall 
exist as described in Section 11.11.2. Fixture or branch drain connections shall not be made to such stacks in 
the suds pressure zones except where relief vents complying with Section 12.15 are provided. Suds-producing 
fixtures include kitchen sinks, laundry sinks, automatic clothes washers, dishwashers, and other fixtures that 
could discharge sudsy detergents. 



2006 National Standard Plumbing Code-Illustrated 



267 



Comment #1: The most likely fixtures to create suds pressure problems in drainage stacks are clothes 
washers, dishwashers, kitchen sinks, and laundry sinks. Where liquid wastes in tall buildings include 
high-sudsing detergents, the detergent is vigorously mixed with the liquid waste and air in the stack. The 
liquid waste is heavier than the suds and does not carry them along with the flow. The suds will settle in 
the lower portions of the drainage system, including any horizontal offsets. The air that is flowing with 
the liquid waste compresses the suds and builds up pressure in the stack that can blow trap seals if not 
relieved. Zones of the drainage and vent piping where suds pressure can exist are described in Section 
11.11.2 and illustrated in Figure 11.11.2. 

Comment #2: Suds pressure relief vents in Section 12.15 are larger than ordinary vents for drainage 
systems because the suds are heavier than air. Suds can weight from 2 to as much as 19 pounds per cubic 

foot. 



1 1.11.2 Locations in Stacks Serving Suds-Producing Fixtures 

a. Zone 1 - at offsets greater than 45 degrees from vertical. A suds pressure zone shall extend 40 pipe 
diameters up the stack above the offset, 10 pipe diameters downstream from the base of the upper portion of 
the stack, and in the horizontal offset, 40 pipe diameters upstream from the top of the lower portion of the 
stack. 

b. Zone 2 - at the base of a soil or waste stack. A suds pressure zone shall extend 40 pipe diameters up 
the stack above its base. 

c. Zone 3 - in the horizontal drain beyond the base of a soil or waste stack. A suds pressure zone shall 
extend 10 pipe diameters from the base of the stack. Also, if a turn greater than 45 degrees occurs in the 
horizontal drain less than 50 feet from the base of the stack, suds pressure zones shall exist 40 pipe diameters 
upstream and 10 pipe diameters downstream from the horizontal turn. 

d. Zone 4 - in a vent stack at the base of a soil or waste stack. Where a vent stack connects above or 
beyond the base of a soil or waste stack, a suds pressure zone shall extend up the vent stack to a level equal 
to the level of the suds pressure zone in the soil or waste stack. 

See Figure 11.11.2 



268 



2006 National Standard Plumbing Code-Illustrated 






ZONE 2: 
ABOVE BASE OF STACK 



ZONE 3: 
BEYOND BASE OF STACK 



ZONE1: 
AT STACK OFFSET GREATER THAN 45° 




VENT 




DRAINAGE STACK 



ZONE 1 OR 2 



TOP OF 
ZONE1 OR 2 



ZONE 3: 

AT TURN GREATER THAN 45° 

WITHIN 50 FEET OF BASE OF STACK 



ZONE 4: 
IN VENT AT BASE OF BASE OF STACK 



Figure 11.11.2 
THE LOCATIONS OF SUDS PRESSURE ZONES IN DRAIN AND VENT PIPING 

11.11.3 Separate Stacks 

Where soil or waste stacks serving suds-producing fixtures extend six or more floors above the base of the 
stack or above a horizontal offset in the stack, the lowest four floors above the base or horizontal offset shall 
be drained by a separate stack. In the case of a horizontal offset, the separate stack for the four floors above 
the offset may be reconnected to the main stack below the offset, provided that the point of connection is not 
a suds pressure zone in either stack. See Figure 11.11.3 



2006 National Standard Plumbing Code-Illustraied 



269 



BUILDING DRAIN - SIZE "D-4' 
I 



T 



NOTE 1 ■ 



OFFSET 
SIZE "D-2' 



8TH 



7TH 



6TH 



5TH 



4TH 



3RD 



2ND 



1 ST 



BSMT 



NOTE 1 



BUILDING DRAIN - SIZE "D-3" 



-I 



T 



16 TH 



15 TH 



14 TH 



13 TH 



12 TH 



11 TH 



10 TH 



9TH 



OFFSET - SIZE "D-1" 



-I 



Figure 11.11.3 

SEPARATE DRAINAGE STACKS FOR LOWER FLOORS 

WHERE THERE ARE SUDS PRODUCING FIXTURES ABOVE 



270 



2006 National Standard Plumbing Code-Illustrated 



NOTES: 



1. 



There should be no branch drain connections within 10 pipe diameters of the base of a drainage 

stack. 



2. Portion D-1 of the upper floor offset between the 8th and 9th floors must be sized as a building 
drain, based on the DFU load for the upper floors above that portion of the offset. 

3. Portion D-2 of the upper floor offset between the 8th and 9th floors must be sized as a building drain 
based on the DFU load for all floors above the offset. 

4. Portion D-3 of the building drain must be sized based on the DFU load for the drainage stack above 
that portion of the building drain. 

5. Portion D-4 of the building drain must be sized based on the DFU for the entire drainage stack. 

Figure 11.11.3 

SEPARATE DRAINAGE STACKS FOR LOWER FLOORS 

WHERE THERE ARE SUDS PRODUCING FIXTURES ABOVE 



11.11.4 Exceptions 

The requirements of Sections 11.11 and 12.15 shall not apply to the following: 

a. Stacks that are less than three stories in height. 

b. Stacks in individual dwellings having their own building sewer. 



2006 National Standard Plumbing Code-Illustrated 271 



Blank Page 



272 



2006 National Standard Plumbing Code-Illustrated 







Vents and Venting 



12.1 MATERIALS 

See Section 3.6. 



12.2 PROTECTION OF TRAP SEALS 

12.2.1 Protection Required 

a. The protection of trap seals from siphonage, aspiration, or back-pressure shall be accomplished by the 
appropriate use of soil or waste stacks with adequate venting in accordance with the requirements of this 
Code. 

b. Venting systems shall be designed and installed so that at no time shall trap seals be subjected to a 
pneumatic pressure differential of more than one inch of water pressure under design load conditions. 

c. If a trap seal is subject to loss by evaporation, means shall be provided to prevent the escape of sewer 
gas. (See Section 5.3.6.) 

See Figures 12.2.1-A and-B 




1" NEGATIVE 
PRESSURE 




- 2" MINIMUM 
TRAP SEAL 




1 1/2" TRAP 

SEAL REMAINS 



NOTES: 

(1 ) Trap at rest with 2" trap seal. 

(2) Trap subjected to 1 " suction from building drainage piping. 

(3) Trap at rest with 1/2" loss of trap seal. Trap will continue to spillover and lose trap seal when 
subjected to 1" suction until the trap seal is reduced to 1". The 2" initial trap seal permits the trap to 
withstand 1 " suction and still maintain a trap seal of at least 1 ". 

Figure 12.2.1 - A 
TRAP SEAL REDUCTION FROM 1" NEGATIVE PRESSURE 



2006 National Standard Plumbing Code-Illustrated 



273 




-2" MINIMUM 
TRAP SEAL 



777777ZZZZAJ ~* 



SPILLOVER WHEN 
PRESSURE REMOVED 
AND FLOW REVERSES 




© 



W/ 






TRAP SEAL ■ 
REMAINS 



2 



(1 ) Trap at rest with 2" trap seal. 

(2) Trap subjected to 1 " positive pressure from building drainage piping. 

(3) When pressure is removed, some spillover occurs from the momentum of the trap legs equalizing. 

(4) Trap will continue to spillover and lose trap seal when subjected to 1 " positive pressure until the trap 
seal is reduced to 1". The 2" initial trap seal permits the trap to withstand 1" positive pressure and 
still maintain a trap seal of at least 1". 

Figure 12.2.1 - B 
TRAP SEAL REDUCTION FROM 1" POSITIVE PRESSURE 



12.3 VENTING OF DRAINAGE STACKS 

12.3.1 Stack Vents and Vent Stacks 

a. A vent stack shall be provided for drainage stacks having five or more branch intervals. 

b. Where drainage stacks have five or more branch intervals, the vent stack shall connect to the drainage 
stack as a relief vent, either: 

1 . To the drainage stack at or below the lowest fixture branch or, 

2. To the building drain within 10 pipe diameters downstream from the base of the stack. 

c. Vent stacks shall also be permitted to be provided for drainage stacks having less than five branch 
intervals. 

See Figure 12.3.1 



274 



2006 National Standard Plumbing Code-Illustrated 



1st BRANCH 
INTERVAL 



2nd BRANCH 
INTERVAL 



3rd BRANCH 
INTERVAL 




4th BRANCH 
INTERVAL 



5th BRANCH 
INTERVAL 



RELIEF VENT CONNECTION 
PER SECTION 12.13.1.b(1) 



BUILDING DRAIN 



> 

A 



--I 



A 



STACK VENT 



• VENT STACK 



1st BRANCH 
INTERVAL 



2nd BRANCH 
INTERVAL 



3rd BRANCH 
INTERVAL 



4th BRANCH 
INTERVAL 



5th BRANCH 
INTERVAL 



RELIEF VENT CONNECTION 
PER SECTION 12.3.1 (2) 



jiLVT R 




\ 



"\ 



A 



STACK VENT 



• VENT STACK 



BUILDING DRAIN "D" 



RELIEF CONNECTION 
TO STACK 



RELIEF CONNECTION 
TO BUILDING DRAIN 



WITHIN 10 X"D" 
PIPE SIZE 



Figure 12.3.1 

VENT STACKS FOR DRAINAGE STACKS 

HAVING 5 OR MORE BRANCH INTERVALS 



12.3.2 Relief Vents for Stacks Having Ten or More Branch Intervals 

a. Where drainage stacks have ten or more branch intervals, a relief vent shall be provided for each ten 
intervals, starting at the top of the stack. 

b. The lower end of each relief vent shall connect to the drainage stack as a yoke vent below its tenth 
branch interval. 

c. The upper end of the relief vent shall connect to the vent stack at an elevation not less than 3 feet 
above the floor level served by the branch interval. 

See Figure 12.3.2 



2006 National Standard Plumbing Code-Illustrated 



275 



V.T.R. 



1ST BRANCH 

INTERVAL 



2ND BRANCH 
INTERVAL 



3RD BRANCH 
INTERVAL 

4TH BRANCH 
INTERVAL 



5TH BRANCH 
INTERVAL 



6TH BRANCH 
INTERVAL 



7TH BRANCH 
INTERVAL 



8TH BRANCH 
INTERVAL 



9TH BRANCH - 
INTERVAL 

10TH BRANCH - 
INTERVAL 

11TH BRANCH - 
INTERVAL 

12TH BRANCH - 
INTERVAL 



13TH BRANCH - 
INTERVAL 



14TH BRANCH - 
INTERVAL 



---I 



A 




/ 



SOIL VENT 
STACK STACK 



10TH BRANCH 
INTERVAL 



-— 5th FLOOR 



/ 



A 



( 



j 



3'MIN 



NOTES: 

1 . A branch interval is the vertical distance between branch connections to a soil or waste stack, 
generally a story height, but never less than 8 feet. The stack has 15 branch intervals. 

2. A relief vent is required for the upper ten branch intervals. 

3. The relief vent connects as a yoke vent below the 6th Floor branch drain connection and connects 
to the vent stack at least 3 feet above the floor on the 6th Floor. 

4. The 3-foot vertical rise in the yoke vent keeps pressure surges in the soil or waste stack from 
causing spill-over of drainage into the vent stack. 

5. Stack relief vents must be the same size as the vent stack. See Section 12.16.4 for sizing vent 
stacks. 

Figure 12.3.2 

RELIEF VENTS FOR DRAINAGE STACKS 

HAVING TEN OR MORE BRANCH INTERVALS 



276 



2006 National Standard Plumbing Code-Illustrated 



12.3.3 Horizontal Offsets 

a. Horizontal offsets in stacks having five or more branch intervals discharging above the offset shall be 
vented either: 

1. by considering the stack as two separate stacks, one above and one below the offset, and venting 
each separately. 

2. by providing a yoke vent from the drainage stack below the offset to the vent stack required by 
Section 12.3.1 not less than 3 feet above the offset. This relief vent may be a stack vent for the lower portion 
of the drainage stack. 

See Figures 12.3.3-A and -B 



V.T.R. I 
ROOF Jk 



TYPICAL FLOOR 



TYPICAL FLOOR 



RELIEF VENT FOR 
UPPER PORTION 
OF STACK 




RELIEF VENT FOR 
LOWER PORTION 
OF STACK 




ALTERNATE RELIEF VENT 
CONNECTED BELOW OFFSET 



- VENT STACK CONNECTION (Note 3) 



-ALTERNATE VENT STACK CONNECTION (Note 3) 

NOTES: 

1. The vent stack must be sized for the entire DFU load on the drain stack per Table 12.16.4. 

2. The relief vents for the upper and lower portions of the drain stack are required to relief backpressure 
from the hydraulic effect of the offset. The relief vents must be the same size as the vent stack. 

3. The vent stack must connect to the base of the drainage stack, either below the lowest branch 
connection above the base of the stack or within 1 pipe diameters downstream from the base of the 
stack. 



Figure 12.3.3 - A 
RELIEF VENTS FOR HORIZONTAL OFFSETS IN DRAINAGE STACKS 

HAVING ONE VENT STACK 



2006 National Standard Plumbing Code-Illustrated 



111 



ROOF 



V.T.R. I 
JlL 



^S 



TYPICAL FLOOR 



TYPICAL FLOOR 



=T 



tq 



VENT STACK FOR 
UPPER PORTION 
OF STACK 



ROOF 



ly.T.R. 



^ 



(Note 5) 



N 



RELIEF VENT (Note 4) 



VENT STACK FOR 
LOWER PORTION 
OF STACK 




ALTERNATE RELIEF VENT 
CONNECTED BELOW OFFSET 



- VENT STACK CONNECTION (Note 5) 



ALTERNATE VENT STACK CONNECTION (Note 5) 



NOTES: 



1. 
2. 



4. 



5. 



The drain stack has separate vent stacks for the upper and lower portions of the stack. 

The vent stack for the upper portion of the drain stack can be sized for only the DFU load on the 
upper portion of the stack. Only vents for upper floor fixtures can be connected to the upper vent 
stack. 

The lower portion of the drain stack carries the DFU load of the upper and lower portions of the 
stack. Its vent stack must be sized for the entire DFU load on the drain stack. 

The relief vent for the lower portion of the drain stack must be the same size as the vent stack for 
the lower portion of the stack. 

The vent stacks must connect to the base of each drainage stack, either below the lowest branch 
connection above the base of the stack or within 1 pipe diameters downstream from the base of the 
stack. 

Figure 12.3.3 - B 

RELIEF VENTS FOR HORIZONTAL OFFSETS IN DRAINAGE STACKS 

HAVING TWO VENT STACKS 



278 



2006 National Standard Plumbing Code-Illustrated 



12.3.4 Vertical Offsets 

Where vertical offsets in drainage stacks having five or more branch intervals above the offset have branch 
connections within 2 feet above or below the offset, a relief vent shall be provided for the lower portion of 
the stack below the offset. 

12.3.5 Vent Headers 

Vents may be connected into a common header at the top of one or more stacks and then be extended to the 
open air at one point. 

12.3.6 Other Use Prohibited 

The plumbing vent system shall not be used for purposes other than venting of the plumbing system. 

12.4 VENT TERMINALS 



12.4.1 Extension Above Roofs 

Vent pipes shall terminate not less than 6 inches above the roof, measured from the highest point where the 
vent intersects the roof. 

EXCEPTION: Where a roof is used for any purpose other than weather protection, vents shall extend at 
least 7 feet above the roof and shall be properly supported. See Figure 12.4.1 




SEALED AGAINST LEAKAGE 
SECTION 4.5, 12.4.2 



FLASHING 
SECTION 12.4.2 



NOTES: 

1. Refer to Section 12.5 for provisions to prevent frost closure. 

Figure 12.4.1 
VENT EXTENSIONS THROUGH THE ROOF 



12.4.2 WaterproofFlashings 

Vent terminals shall be made watertight with the roof by proper flashing. 

12.4.3 Flag Poling Prohibited 

Vent terminals shall not be used for the purpose of flag poling, TV aerials, or similar purposes. 



2006 National Standard Plumbing Code-Illustrated 



279 



12 A A Location of Vent Terminal 

a. Vent terminals shall not be located where vapors can enter the building. 

b. No vent terminal shall be located directly beneath any door, window, or other ventilating opening of a 
building or of another building, nor shall any such vent terminal be within 10 feet horizontally of such opening 
unless it is at least 2 feet above the top of such opening. 

c. Where a vent terminal is within 10 feet horizontally and less than 2 feet above a ventilation opening 
described in Section 12.4.4b and the line-of-sight from the vent terminal to the ventilation opening is inter- 
rupted by the continuous ridge of a roof, the ridge shall be at least 2 feet above the top of the opening. Other- 
wise, the vent terminal shall comply with Section 12.4.4b. 

d. Where a vent terminal is within 10 feet horizontally and less than 2 feet above a ventilation opening 
described in Section 12.4.4b and the line of sight from the vent terminal to such ventilation opening is inter- 
rupted by a solid wall or solid barrier, the top of the wall or barrier shall be at least 2 feet above the top of the 
ventilation opening and the shortest travel distance around the wall or barrier from the vent terminal to the 
nearest edge of the ventilation opening shall be at least 10 feet. Otherwise, the vent terminal shall comply 
with Section 12.4.4b. 

See Figure 12.4.4 




AIR INTAKE OR 
EXHAUST OPENING 

NOTES: 

1 . The separation of vent terminals from doors, windows, and air intake and exhaust openings keeps 
foul odors from entering the building. 

2. The vent terminal is less than 2 feet above the window, but the window is 1 feet or more from the 
vent terminal horizontally. 

3. The air intake or exhaust opening can be within 1 feet horizontally from the vent terminal if the vent 
terminal is 2 feet or more above the top of the opening. 



Figure 12.4.4 
ALLOWABLE LOCATIONS FOR VENT TERMINALS 

12.4.5 Sidewall Venting 

Vent terminals shall be permitted to extend through a wall on an existing building. They shall be at least 10 
feet horizontally from any lot line, 10 feet above existing grade, and terminate with a corrosion-resistant bird 



280 



2006 National Standard Plumbing Code-Illustrated 



screen. Vent terminals shall not terminate under an overhang of a building. They shall be located in 
accordance with Section 12.4.4. 

12.4.6 Extensions Outside Building 

No soil, waste, or vent pipe extension shall be installed on the outside of a wall of any new building, but 
shall be carried up inside the building ' 

EXCEPTION: In those localities where the outdoor temperature does not drop below 32°F, the Authority 
Having Jurisdiction may approve the installation outside the building. 

12.4.7 Flashing Roof Vent Terminals 

a. Vent terminals through the roof shall be made watertight to the roof by sealing the flashing to either 
the exterior or interior of the vent terminal. 

b. Vent terminals that are externally sealed shall employ manufactured vent stack flashing sleeves, 
roof couplings, or no-caulk roof vent flashings. 

c. Where vent terminals are sealed by counter-flashing over the top of the vent terminal, the counter 
flashing shall not decrease the interior free area of the minimum required vent terminal size. Vent 
terminals shall be increased at least one pipe size when counter-flashed. Interior counter flashing shall be 
sealed gas-tight to prevent the entrance of sewer gas into the building through the flashing. 

12.5 FROST CLOSURE 

Where the Authority Having Jurisdiction requires protection against frost closure, vent terminals less 
than 3" pipe size shall be increased at least one pipe size to not less than 2" size. Where an increase is 
necessary, the increase in size shall be made inside the building at least one foot below a roof or ceiling 
that is thermally insulated and in an area not subject to freezing temperatures. See Figure 12.5 



MINIMUM 3" SIZE 



SEALED 

WATERPROOF 

FLASHING 



NOTE: 




ROOF 



INCREASER FITTING 
WHERE NECESSARY 



VENT SIZE (See Table 12.16) 



1 . Where pipe size increases are necessary to avoid frost closure, the increase in pipe size must 
be one foot below an area subject to freezing temperatures. 

Figure 12.5 
MINIMUM VENT EXTENSION SIZE TO PREVENT FROST CLOSURE 



2006 National Standard Plumbing Code-Illustrated 



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12.6 VENT SLOPES AND CONNECTIONS 



12.6.1 Vent Slope 

Vent and branch vent pipes shall be free from drops and sags and be sloped and connected as to drain by 
gravity to the drainage system. See Figure 12.6.1 







VENT MUST NOT 7 , 
FORM A TRAP / 




1 




BEAM —7 / 




r f — — 






"U 


"U 


^ 


\ 


v 


\ 


BACKWARD SLOPE 


FORWARD SLOPE 



NOTE: 

1 . Vent piping that is sloped allows condensation and moisture that may form in the piping to drain to 
the drainage system. 

2. Vent piping must not have any trapped sections. Water may collect in trapped piping, fill the piping, 
and renderthe vent ineffective. 

3. Vent piping can slope back to the fixture served or forward away from the fixture, as long as it drains 
to the drainage system. 

Figure 12.6.1 
VENT PIPING SLOPE 



12.6.2 Vertical Rise 

Every vent shall rise vertically to a minimum of 6 inches above the flood level of the rim of the fixture being 

served before connecting to a vent. 

EXCEPTION: 

If a horizontal offset is required in the verticle rise due to existing conditions the horizontal section shall be 

installed in accordance with sec. 12.6.2.2. 

See Figure 12.6.2-A and-B 



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2006 National Standard Plumbing Code-Illustrated 




CONNECT VENT TO 
SOIL OR WASTE PIPING 
ABOVE CENTERLINE 



CENTERLINEOFTHE 
SOIL OR WASTE PIPE 




■ HORIZONTAL DRAIN 

MUST BE ABOVE 
CENTER LINE 

NOTES: 

1 . Connecting the vent above the centerline of a horizontal drain reduces the possibility of the vent 
connection being fouled by the flow in the drain. 

Figure 12.6.2 - A 
VENT PIPE CONNECTIONS TO HORIZONTAL DRAINS 



FLOOD LEVEL RIM OF LAVATORY 



STACK 
VENT 




See EXCEPTION 
in Section 12.6.2 



BATHTUB 



TRAP ARM 
(Notel) 

NOTES: 

1 . A separate vent will be required for the bathtub if the developed length of its trap arm exceeds the 
maximum allowable length in Table 12.8.1 . 

2. If a vent is required for the bathtub, it can have a horizontal offset below the flood level rim of the 
bathtub, but it must be 6 inches above the flood level rim of the lavatory before it connects to another 
vent. The horizontal offset below the flood level rim must be sloped so that it drains to the drainage 
system. 



Figure 12.6.2 - B 

HORIZONTAL VENT PIPING 

BELOW THE FLOOD LEVEL RIM OF FIXTURES 



12.6.2.1 

Where a vent pipe connects to a horizontal fixture drain branch, and conditions require a horizontal 
offset in the vent below the flood level rim of the fixture served, the vent shall be taken off so that the 
invert of the horizontal portion of the vent pipe is at or above the centerline of the horizontal soil or 
waste pipe. 



2006 National Standard Plumbing Code-Illustrated 



283 



12.6.2.2 

The portion of the horizontal vent installed below the flood level rim as permitted in Section 12.6.2. 1 
shall be installed with the required slope to drain by gravity to the drainage system. See Figure 
12.6.2 -B 

12.6.2.3 

Cleanouts shall be provided in the vent piping so that any blockages in the vent piping below the flood 
level rim of the fixture served can be cleared into the drainage system. 

12.6.3 Vent Connection Height Above Fixtures 

Connections between any horizontal vent pipe, including individual vents, branch vents, relief vents, circuit 
vents or loop vents, and a vent stack or stack vent shall be made at least 6 inches above the flood level rim of 
the highest fixture on the floor level. 

12.6.4 Side-Inlet Closet Bends 

a. Side-inlet closet bends shall be permitted only in cases where the fixture connection thereto is vented. 

b. In no case shall the side-inlet be used to vent a bathroom group without being washed by a fixture. 
EXCEPTION: As allowed in Sections 12.10 and 12.1 1. 

12.7 ADJACENT FIXTURES 

Two fixtures set adjacent within the distance allowed between a trap and its vent, may be served with one com- 
mon vent, provided that each fixture connects separately into an approved double fitting having inlet openings at 
the same level. (See Section 12.9.2 for inlet openings at different levels.) See Figure 12.7 



Comment: Suitable double fittings for connecting adjacent fixtures such as lavatories, sinks, tubs, showers, 
urinals, or floor-outlet water closets to a stack are double sanitary tees, double fixture fittings (plastic), and 
sanitary crosses. These fittings have high branch openings into the stack that keep the top of the vent 
opening above the weir of the traps to prevent self-sip honage. 




COMMON VENT 



SANITARY CROSS OR 
DOUBLE SANITARY TEE 



Figure 12.7 

VENTING ADJACENT FIXTURES 

CONNECTED TO A VERTICAL DRAIN AT THE SAME LEVEL 



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2006 National Standard Plumbing Code-Illustrated 



12.8 FIXTURE VENTS 

12.8.1 Venting of Fixture Drains 

Fixture drains shall have a vent so located that the vent connects above the top weir of the trap and the 

developed length of the trap arm is within the limits set forth in Table 12 8 1 

EXCEPTIONS: 

(1) Water closets and similar siphonic fixtures. 

(2) Combination waste and vent systems, (see Section 12.17) 

(3) Vents may be connected below the top weir of the fixture trap if the following conditions are met: 

a) The vertical section of the drain pipe shall be at least one pipe size larger than the trap inlet size 

b) The horizontal pipe connected to the trap outlet shall be at least two pipe diameters long. 

c) The developed length of the trap arm shall not exceed the values in Table 12 8 1 
See Figures 12.8.1-A and-B 




VENT 



INSIDE WALL OF PIPE 
TOP OF VENT OPENING 

- WASTE 



NOTES: 



1. 
2. 



Trap arm lengths are limited by Table 12.8.1 to prevent self-siphonage of the fixture trap. 
The top of the opening at the vent pipe must not be below the elevation of the trap weir. The 
maximum trap arm lengths in Table 1 2.8.1 are based on using sanitary tees or other short turn 
fittings to connect trap arms to the drainage system. Long turn fittings should not be used with 
Table 12.8.1. 

The trap arm length is the developed length along its centerline, including any changes in direction. 

Figure 12.8.1 - A 
THE MAXIMUM LENGTH OF TRAP ARMS 



Table 12.8.1 
MAXIMUM LENGTH OF TRAP ARM 



Diameter of Trap 
Arm (Inches) 



Length — Trap to Vent 



Slope — Inches per Foot 



Vh 

2 
3 
4 



3'6" 

5' 
8' 
10' 
12' 



NOTE: This table has been expanded in the "length" requirements to reflect expanded application of the wet venting principles Slope shall not 
exceed 1/4" per foot. 



2006 National Standard Plumbing Code-Illustrated 



285 



VENT 




VENT 



k 



VENT VENT 
CONNECTED | 




."C" 



"D" 




EXAMPLE OF 
EXCEPTION #3 



EXAMPLE OF 
EXCEPTION #3 



NORMAL VENT 
CONNECTION 



NOTES: 

1 . "A" is the trap pipe size. 

2. "B" is the horizontal pipe between the trap outlet and the vertical leg. Its length must be at least 
two times the trap pipe size to avoid creating an "S" trap. 

3. "C" is the vertical drop. It must be one size larger than the trap pipe size. 

4. "D" is the connection to a vented drain line. The horizontal portion of "D" must be the same size as 
"C". The distance from the weir of the trap to the vent connection at "D" must be within the limits of 
Table 12.8.1, based on the size of the trap. 

Figure 12.8.1 - B 

EXAMPLES OF EXCEPTION #3 TO SECTION 12.8.1 

(VENT CONNECTIONS BELOW THE WEIR OF A TRAP) 

12.8.2 Provision for Venting Future Fixtures 

On new construction of residential dwelling units with basements, a 2" minimum size vent shall be installed 
between the basement and attic or tied into an existing, properly sized vent and capped for future use. 

12.8.3 Crown Venting Limitation 

A vent shall not be installed within two pipe diameters of the trap weir. See Figure 12.8.3 



VENT 



INSIDE WALL OF PIPE 




TRAP WEIR 



WASTE 



NOTES: 

1 . Vents connected too close to the crown or weir of a trap are subject to clogging, thereby rendering 
the vent ineffective. Vent connections must be at least two pipe diameters from the weir of the trap. 



Figure 12.8.3 
CROWN VENTS ARE PROHIBITED 



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2006 National Standard Plumbing Code-Illustrated 



12.8.4 Water Closets and Other Siphonic Fixtures 

For water closets and other fixtures that operate by siphonic action, the distance between the outlet of the 
fixture and its vent connection shall not exceed 3 feet vertically and 9 feet horizontally. 

12.9 COMMON VENTS 



1 2.9. 1 Individual Vent as Common Vent 

An individual vent, installed vertically, may be used as a common vent for two fixture traps when both fixture 
drains connect with a vertical drain at the same level. 

12.9.2 Fixtures Drains Connected at Different Levels 

A common vent may be used for two fixtures installed on the same floor but connecting to a vertical drain at 
different levels, provided that the vertical drain is one pipe size larger than the upper fixture drain but in no 
case smaller than the lower fixture drain. See Figure 12.9.2 



1 DFU 



3DFU 



£ 



1 1/4" 



NOT LESS THAN 1 1/2" 



COMMON VENT 
1 DFU 



J? 



-COMMON VENT 



3" (Note 1) 



1 1/4" 



2" 






1 DFU 


_^r 




3" "v. 


/ XT"" 



1 1/4" 



1 DFU 



1 1/4" 



C 



\/~ 



COMMON VENT 



3 DFU 



2" 



^r 



2" (Note 1)- 



NOTES: 

1 . When the upper fixture is 3 DFU and the lower is 1 DFU, the vertical drain must be 3" instead of 2" 
so that the 1 DFU fixture is wet vented during the heavier discharge from the 3 DFU fixture. 

Figure 12.9.2 

VENTING FIXTURES CONNECTED TO A 

VERTICAL DRAIN AT DIFFERENT LEVELS 



12.10 WET VENTING 

12.10.1 Single Bathroom Groups 

a. An individually vented lavatory in a single bathroom group shall be permitted to serve as a wet vent for 
either the water closet, the bathtub or shower stall, the water closet and bathtub/shower if all of the following 
conditions are met. 

1 . The wet vent is 1-1/2" minimum pipe size if the water closet bend is 3" size or it shall be 2" minimum 
pipe size if the water closet bend is 4" pipe size. 

2. A horizontal branch drain serving both the lavatory and the bathtub or shower stall is 2" minimum pipe 
size. 



2006 National Standard Plumbing Code-Illustrated 



287 



3. The length of the trap arm for the bathtub or shower stall is within the limits of Table 12.8.1 . If not, the 
bathtub or shower stall shall be individually vented. 

4. The distance from the outlet of the water closet to the connection of the wet vent is within the limits 
established by Section 12.8.4. Otherwise, the water closet shall be individually vented. 

5. A horizontal branch serving the lavatory and the bathtub or shower stall shall connect to the stack at 
the same level as the water closet, or it may connect to the water closet bend, or the lavatory and bathtub or 
shower stall may individually connect to the water closet bend. 

6. When the bathroom group is the topmost load on a stack, a horizontal branch serving the lavatory and 
the bathtub or shower stall may connect to the stack below the water closet bend, or the lavatory and the 
bathtub or shower stall may individually connect to the stack below the water closet bend. 

See Figures 12.10.1-A through-C 

/I 

1 1/2" 



STACK - 
VENT 




- 2" MIN 
I WATER CLOSET 



TUB/SHOWER 



5'-0" IF 1 1/2" 
8'-0" IF 2" 



NOTES: 

1 . The vent for the bathroom group is 1-1/2", which is 1 12 the size of the 3" drain for the bathroom 
group. 

Figure 12.10.1 - A 

A WET VENTED BATHROOM GROUP WITH A 3" CLOSET BEND 

(SINGLE STORY OR TOP FLOOR) 



STACK 
VENT 




TUB/SHOWER 



5'-0" MAX IF 1 1/2" 
8'-0" MAX IF 2" 



WATER CLOSET 



NOTES: 

1 . The vent for the bathroom group is 2", which is 1/2 the size of the 4" drain for the bathroom group. 
Even though the bathroom group could have had a 3" drain with a 1-1/2" vent, installing a 1-1/2" vent 
on the 4" drain would cause unnecessary confusion for the installer and inspector. 

Figure 12.10.1 - B 

A WET VENTED BATHROOM GROUP WITH A 4" CLOSET BEND 

(SINGLE STORY OR TOP FLOOR) 



288 



2006 National Standard Plumbing Code-Illustrated 



STACK - 
VENT 




TUB/SHOWER 



5'-0" MAX IF 1 1/2" 
8'-0" MAX IF 2" 



WATER CLOSET 



Figure 12.10.1 - C 

A WET VENTED BATHROOM GROUP WITH 3" OR 4" CLOSET BEND 

(SINGLE STORY OR TOP FLOOR) 

12.10.2 Double Bathtubs and Lavatories 

Two lavatories and two bathtubs or showers back-to-back may be installed on the same horizontal branch 
with a common vent for the lavatories and with no back vent for the bathtubs or shower stalls provided the 
wet vent is 2" in size and the lengths of the tub/shower drains conform to Table 12.8.1. See Figure 12.10.2 



WATER CLOSET 



T _2" 



LAVATORY 



TUB 




MAX IF 1 1/2" 
MAX IF 2" 



WATER CLOSET 



Figure 12.10.2 

WET VENTED BACK-TO-BACK BATHROOM GROUPS 

(SINGLE STORY OR TOP FLOOR) 

12.10.3 Multi-Story Bathroom Groups 

a. On the lower floors of a stack, the waste pipe from one or two lavatories may be used as a wet vent for 
one or two bathtubs or showers as provided in Section 12.10.2. 

b. Each water closet below the top floor shall be individually back vented. 

EXCEPTION: The water closets in bathroom groups shall not be required to be back vented if the follow- 
ing conditions are met: 



2006 National Standard Plumbing Code-Illustrated 



289 



1. The 2" waste serving the tubs/showers and lavatories connect directly into the water closet bend with a 
45° wye tap in the direction of flow or, 

2. A special stack fitting is used that consists of a 3" or 4" closet opening and two side inlets each 2" in 
size and the inverts of which are above the center, and below the top of the water closet opening; and one of 
the 2" inlets is connected to the tub/shower drains, and the other is connected to the waste pipe from a 
maximum of two lavatories that are vented to a vent stack or stack vent; or, 

3. In lieu of the special stack fitting of Section 12.10.3b(2) above, 4" closet bends with two 2" wye taps 
may be used. 

See Figures 12.10.3-A through-E 



INDIVIDUAL 
BACK VENTS 



WATER CLOSET 



SOIL STACK 




•VENT 
STACK 



LAVATORY t 
TUB/SHOWER 

TUB/SHOWER 



WATER CLOSET 



Figure 12.10.3 - A 

WET VENTED BACK-TO-BACK BATHROOM GROUPS ON A LOWER FLOOR 

WITH BACK VENTED WATER CLOSETS 

(ONE ARRANGEMENT) 



290 



2006 National Standard Plumbing Code-Illustrated 



VENT- 




5'-0" MAX IF 1 1/2" 
8'-0" MAX IF 2" 



SOIL STACK- 



WATER 
CLOSET 



Figure 12.10.3 - B 

WET VENTED BACK-TO-BACK BATHROOM GROUPS ON A LOWER FLOOR 

WITH BACK VENTED WATER CLOSETS 

(ANOTHER ARRANGEMENT) 



WATER 
CLOSET 



lavatory' tub/ 

lAj SHOWER 



A 



-2" I 




-VENT 
STACK 



TUB/SHOWER 



5'-0" MAX IF 1 1/2" 
8'-0" MAX IF 2" 



3" OR 4" 
CLOSET BEND 

NOTES: 

1 . This is an example of Exception #1 to Section 12.10.3. 

2. Two adjacent bathroom groups are shown but individual bathroom groups can also be wet vented in 
this manner. 

3. A lower floor is shown, but the arrangement can be used at the top of a stack. 

Figure 12.10.3 - C 
ADJACENT BATHROOM GROUPS WET VENTED WITH 45 DEGREE WYE TAPS 



2006 National Standard Plumbing Code-Illustrated 



291 



r 



i/ 4 " 




LAV. 

2" 



- VENT STACK 



STJO 




iy 2 " TRAP 



DETAIL OF 
HUBLESS 
SPECIAL 
STACK FITTING 



SPECIAL 

STACK 

FITTING 



NOTES: 

1. This is an example of Exception #2 to Section 12.10.3. 

2. The side inlets to the special stack fitting are slightly higher than the water closet connection and 
the side connection that is wet vented vents all of the fixtures that are connected to the fitting. 

3. A lower floor is shown, but the special stack fitting can be used at the top of a stack. 

Figure 12.10.3 -D 
A BATHROOM GROUP WET VENTED WITH A SPECIAL STACK FITTING 



w.c. 








T 






i 




2 "\ 

X 


■» ' i 

^ s I 


,- VENT STACK 


4 
1%; 


\ 




LAV iA 


"I I 




I I 

2" I I 






\j «■ | 








/ * 




yC — 


2" 


\j LAV 





1/2" TUB/ SHOWER TRAP 



1/2" TUB/ SHOWER TRAP 

NOTES: 

1. This is an example of Exception #3 to Section 12.10.3. 

2. The oversized 4" water closet fixture drain permits the tub/shower on one side of the drain to be wet 
vented by the lavatory on the other side of the drain. 

3. Two adjacent bathroom groups are shown, but individual bathroom groups can be wet vented in this 
manner. 

4. A lower floor is shown, but the arrangement can be used at the top of a stack. 

Figure 12.10.3 -E 
ADJACENT BATHROOM GROUPS WET VENTED WITH 4" CLOSET BENDS 

HAVING TWO 2" WYE TAPS 



292 



2006 National Standard Plumbing Code-Illustrated 



12.10.4 Bathtubs and Water Closets 

a. An individually-vented bathtub in a single bathroom group shall be permitted to serve as a wet vent for 
the water closet if all of the following conditions are met: 

1 . The wet vent is 2" minimum size. 

2. The distance from the outlet of the water closet to the connection of the wet vent is within the limits 
established by Section 12.8.4. Otherwise, the water closet shall be individually vented. 

See Figure 12.10.4 



SOIL OR 
WASTE STACK 



SOIL STACK 




1#" FOR 3" CLOSET BEND OR BRANCH 
2" FOR 4" CLOSET BEND OR BRANCH 



TUB/SHOWER 
1X2" TRAP 



2" WET VENT 



WATER CLOSET 
(Note 1) 



3" OR 4' 



NOTES: 

1 . The maximum distance from the water closet outlet to its vent connection is 9 feet horizontal and 3 
feetvertical. 

2. A lower floor is shown, but the arrangement can be used at top of stack. 

Figure 12.10.4 
A WATER CLOSET WET VENTED BY A BATHTUB 



12.10.5 Waste Stacks in Dwelling Units 

In a single dwelling unit, a waste stack that receives the discharge of a kitchen type sink or a 3 dfu fixture 
may also serve as a wet vent for a laundry tray or a 3 dfu fixture connected to the stack at the floor below. 
The minimum size of the waste stack and wet vent up to the upper branch connection shall be 2" in diameter. 
No sink shall be installed on a two-inch wet vent that vents a water closet. See Figure 12.10.5 



2006 National Standard Plumbing Code-Illustrated 



293 



V 



i 



UPPER FLOOR 



i 



LOWER FLOOR 



r 



-1)4" MINIMUM 



KITCHEN SINK 

OR OTHER FIXTURE UP TO 3 D.F.U. 

(EXCEPT A WATER CLOSET) 



4 



2" WET VENT (MIN.) 



LAUNDRY TRAY 
OR OTHER FIXTURE 
(3 D.F.U. MAXIMUM) 



i 



NOTES: 

1 . The arrangement is limited to waste stacks in dwelling units, and cannot serve water closets. 

Figure 12.10.5 
WASTE STACKS IN DWELLING UNITS 



12.11 STACK VENTING 

12.11.1 Fixture Groups 

a. A single bathroom group and a kitchen sink (with or without a disposer and/or dishwasher) located back- 
to-back, or two bathroom groups back-to-back may be installed without individual fixture vents in a one-story 
building or on the highest branch of a stack provided that the following conditions are met: 

1. Each fixture drain connects independently to the stack. 

2. The tub and/or shower and water closet enter the stack at the same level. 

3. The requirements of Table 12.8.1 are met. 

4. A side inlet connection into a 4" closet bend shall be considered to be an independent connection to the 
stack. 

See Figures 12.11. 1-A and-B 



294 



2006 National Standard Plumbing Code-Illustrated 




LAVATORY 



4" CLOSET BEND 
WATER CLOSET 



TUB / SHOWER 



STACK 

NOTES: 

1 . The arrangement shown is permitted in a one-story building or at the top of a stack. 

2. Each fixture must connect independently to the stack except that the tub/shower connection to the 
4" water closet fixture drain is considered to be a connection to the stack because the 4" drain is 
oversized for the water closet. 

3. The length of all trap arms from their trap weir to their vent opening at the stack must not exceed 
the limits in Table 12.8.1. The vent distance for the water closet must be in accordance with 
Section 12.8.4. 
Bathroom groups without kitchen sinks can also be stack vented as shown. 



4. 



Figure 12.11.1 - A 

STACK VENTING A BATHROOM GROUP AND AN ADJACENT KITCHEN SINK 



VENT THRU ROOF 
I 



KITCHEN I. iy 2 " 
SINK 



TUB / SHOWER 




LAVATORY 



4" CLOSET BEND 



NOTES: 

1 . The arrangement shown is permitted in a one-story building or at the top of a stack. 

Each fixture must connect independently to the stack except that the tub/shower connections to 
the 4" water closet fixture drains are considered to be connections to the stack because the 4" 
drains are oversized for the water closets. 

The length of all trap arms from their trap weir to their vent opening at the stack must not exceed 
the limits in Table 1 2 .8. 1 . The vent distance for the water closets must be in accordance with 
Section 12.8.4. 

4. Bathroom groups without kitchen sinks can also be stack vented as shown. 



2. 



3. 



Figure 12.11.1 - B 
STACK VENTING ADJACENT BATHROOM GROUPS AND AN ADJACENT KITCHEN SINK 



2006 National Standard Plumbing Code-Illustrated 



295 



12.11.2 LowerFloors 

a. Lower floor bathroom groups may be vented as provided in Section 12.11.1, provided the following 
conditions are met: 

1 . A wye is installed in the stack with an upright one-eighth bend continuing from the wye branch to serve 
the stack group. 

2. A 2" relief vent is connected to the wye branch at least 6 inches above the flood level rim of the 
highest fixture on the wye branch. 

See Figures 12.11.2-A and-B 



STACK 



VENT STACK 



LAVATORY 



TUB / SHOWER 




FLOOD LEVEL RIM 
OF HIGHEST FIXTURE 



WATER CLOSET 

WITH 4" FIXTURE DRAIN 



STACK WYE WITH UPRIGHT Y s BEND 



NOTES: 

1 . Each fixture in the stack group must connect independently to the sub-stack except that the 
connection to the 4" water closet fixture drain is considered to be a connection to the sub-stack 
because it is oversized for the water closet. 

2. The length of all trap arms from their trap weir to their stack must not exceed the limits in Table 
1 2.8.1 . The vent distance for the water closet must be in accordance with Section 12.8.4. 

Figure 12.11.2 - A 
STACK VENTING A BATHROOM GROUP ON A LOWER FLOOR OF A DRAIN STACK 



296 



2006 National Standard Plumbing Code-Illustrated 



VENT j 

THRU 

ROOF 



TUB/SHOWER 



TUB/SHOWER 



TUB/SHOWER 



TUB/SHOWER 




STACK VENTED 
TOP FLOOR 



STACK VENTED 
LOWER FLOOR 



STACK VENTED 
LOWER FLOOR 



WET VENTED 
LOWER FLOOR 



Figure 12.11.2 - B 
STACK VENTED AND WET VENTED BATHROOM GROUPS ON A DRAIN STACK 



12.12 FIXTURE REVENTING 



12.12.1 Reserved 

12.12.2 Horizontal Branches 

Three lavatories or one sink within 8 feet developed length of a main-vented line may be installed on a 2" 
horizontal waste branch without reventing, provided the branch is not less than 2 inches in diameter through- 
out its length, and provided the wastes are connected into the side of the branch and the branch leads to its 
stack connection with a grade of not more than 1/4 inch per foot. See Figure 12.12.2 



2006 National Standard Plumbing Code-Illustrated 



297 



STACK VENT 




-NOT MORE THAN 
y 4 " PER FOOT SLOPE 



WYE IN STACK WITH UPRIGHT % BEND 



VENT 
STACK 



NOTES: 

1 . The horizontal branch must have not more than 8 feet developed length, be 2" minimum size, and 
be sloped not more than 1/4" per foot to avoid self-siphonage of the fixture trap. 

Figure 12.12.2 
FIXTURES ON HORIZONTAL BRANCHES OF A STACK WITHOUT REVENTS 

12.12.3 Fixtures without Revents Above Highest Bathtubs and Water Closets 

a. Fixtures without revents may be connected to a soil or waste stack above the highest water closet or 
bathtub connection if all the following conditions are met: 

1 . The total load does not exceed 3 dfu's. 

2. The soil or waste stack is 3" or larger. 

3. The total load on the stack is in accordance with Table 1 1.5. IB. 

4. The waste piping of the fixture above the water closet or bathtub connection is in accordance with 
Sections 12.8.1 and 12.12.2. 

See Figure 12.12.3 



298 



2006 National Standard Plumbing Code-Illustrated 




2nd FLR 



IstFLR 



BATHROOM 
GROUP 



? 



STACK "A" 



3" 



BUILDING DRAIN 

NOTES: 

1 . One or more fixtures totaling up to 3 DFU can be connected to a 3" minimum stack above the highest 
bathtub orwater closet without individual vents (revents) if the horizontal waste branch(s) from the 
fixture(s) is 2" size with 8 feet maximum developed length and sloped no more than 1/4" per foot. 

2. The stack must be larger than 3" size if required by Table 1 1 .5.1 .B. 

Figure 12.12.3 
UNVENTED FIXTURES ABOVE THE HIGHEST BATHTUBS AND WATER CLOSETS 

12.12.4 VentWashdown 

a. Fixtures other than kitchen sinks or food-waste-grinders shall be permitted to wash down a vertical loop 
vent, circuit vent or relief vent associated with a battery-vented horizontal soil or waste branch without 
reventing, provided that: 

1. Not more than 2 drainage fixture units are drained to a 2" vent, nor more than 4 drainage fixture units are 
drained to a 3" vent; 

2. The fixture trap arm lengths comply with Section 12.8.1; 

3. The fixtures drained to the vent are within the same branch as the other fixtures served by the vent; and 

4. No other fixtures are drained to the vent. 



2006 National Standard Plumbing Code-Illustrated 



299 



12.13 CIRCUIT AND LOOP VENTING 

12.13.1 Battery Venting 

a. A maximum of eight floor-outlet water closets, showers, bathtubs, or floor drains connected in battery 
on a horizontal branch drain shall be permitted to be battery vented. 

EXCEPTION: Blowout type water closets. 

b. Each fixture drain shall connect horizontally to the horizontal branch drain being so vented. 

c. The horizontal branch drain shall be considered as a vent extending from the most downstream fixture 
drain connection to the most upstream fixture drain connection. 

d. Back-outlet water closets shall be permitted to be battery vented provided than no floor-outlet fixtures 
are connected to the same horizontal branch drain. 

EXCEPTION: Back-outlet blowout type water closets. 

e. The battery vent shall be a circuit or loop vent connected to the horizontal branch drain between the two 
most upstream fixture drains and shall be installed in accordance with Section 12.6. 

f. The entire length of the vent section of the horizontal branch drain shall be uniformly size for the total 
drainage discharge connected thereto. 

g. The maximum slope of the horizontal branch drain shall be 1 inch per foot. 

h. A relief vent shall be provided on battery-vented horizontal branch drains on lower floors that have four , 
or more water closets connected. 

i. The relief vent shall connect to the horizontal branch drain between the stack and the most downstream 
fixture drain connection. 

j. Relief vents shall be installed in accordance with Section 12.6. 

k. Circuit, loop, and relief vents shall be permitted to be a fixture drain or fixture branch for fixtures 
located within the same branch interval as the battery-vented horizontal branch drain. 
EXCEPTION: No more than four drainage fixture units (DFU) shall discharge to the vent. (See Section 
12.12.4). 

1. Lavatories and similar fixtures shall be permitted to connect to the horizontal branch drain, either hori- 
zontally or vertically. 
EXCEPTIONS: 

(1) Fixtures that are not located on the same floor as the battery-vented fixtures. 

(2) Fixtures that do not have an individual, common, or continuous vent. 

m. Batteries of more than eight battery-vented fixtures shall have a circuit or loop vent for each group of 
eight or less fixtures. 

n. Where there are two or more groups of battery-vented fixtures, the horizontal branch drain for each 
downstream group shall be sized for the total discharge into that group, including all upstream groups and the 
fixtures within the group being sized. 
See Figure 12.13.1 and the definitions of "Battery of Fixtures", "Vent, Circuit", and "Vent, Loop". 



300 



2006 National Standard Plumbing Code-Illustrated 



LOOP VENT 



T VENT 
'/""STACK 



RELIEF 
VENT 




CIRCUIT VENT 



CIRCUIT VENT 



NOTE 8 






00= 


J-^ 


BACK OUTLET FIXTURE 



RELIEF VENT 
NOT REQUIRED 



RELIEF VENT 
NOT REQUIRED 



NOTES: 

1 . Battery vented horizontal branch drains can serve a mixture of two to eight water closets, floor 
drains, bathtubs, shower stalls, and other floor-outlet fixtures. 

2. Battery vented fixtures must connect horizontally to the horizontal branch drain. 

3. The entire length of the horizontal branch drain must be sized for the total DFU load for the branch 
The slope of the drain must not exceed 1" per foot. 

4. The developed length of fixture trap arms must be within the limits of Table 12 8 1 for the qiven pine 
size. K 

5. Lavatories, sinks, and wall-mounted urinals can connect horizontally or vertically to the horizontal 
branch drain, but they must be independently vented. 

6. Relief vents are required where horizontal branch drains on lower floors serve more than four water 
closets. 

7. Fixtures are permitted to drain into circuit, loop and relief vents. A 2" vent can drain 2 DFU A 3" 
vent can drain 4 DFU. 

8. Back outlet water closets and wall mounted urinals that are battery vented must connect horizon- 
tally to the horizontal drain branch. 



Figure 12.13.1 
CIRCUIT AND LOOP VENTING BATTERIES OF FIXTURES 



2006 National Standard Plumbing Code-Illustrated 



301 



12.13.2 JoiningParallel Branches 

Where parallel branches of up to eight battery-vented fixtures each are joined prior to connecting to a stack 
or building drain, the common downstream piping shall be sized for the combined total fixture unit load of 
both branches. A relief vent shall be provided on the common downstream piping when the parallel branches 
serve a combined total of four or more water closets and connect to a stack receiving drainage from an 
upper floor. 

12.13.3 Vent Connections 

Circuit, loop, and relief vent connections to battery-vented horizontal drain branches shall be taken off at a 
vertical angle or from the top of the horizontal drain. See Section 12.6.2. 

12.13.4 Fixtures Back-to-Back in Battery 

When fixtures are connected to one horizontal branch through a double wye or a sanitary tee in a vertical 
position, a common vent for each two fixtures back-to-back or double connection shall be provided. The 
common vent shall be installed in a vertical position as a continuation of the double connection. 

12.14 VENTING OF BUILDING SUBDRAIN SYSTEMS 

12.14.1 Fixture Venting 

Fixtures and gravity drainage piping in a building subdrain system shall be vented in the same manner as a 
conventional gravity drainage system and shall be permitted to connect to vent piping for fixtures and gravity 
drainage piping that are not part of the subdrain system. 

12.14.2 SumpPits 

a. The minimum size and maximum length of vents for atmospheric sump pits shall be as indicated in Table 
12.14.2 

b. Where subdrain systems utilize pneumatic sewage ejectors, atmospheric sump pits or surge tanks shall be 
provided if water closets, urinals, or other fixtures are close enough to the ejector that they will overflow if flushed 
while the ejector is discharging. 

c. The atmospheric vents from sump pits and surge tanks shall be permitted to be connected to gravity vent 
piping for fixtures other than those served by the sump pit. 



302 2006 National Standard Plumbing Code-illustrated 



Table 12.14.2 
SIZE AND LENGTH 1 OF SUMP VENTS 



Diameter of Vent, (inches) 

Discharge Capacity 1-1/4 1-1/2 2 2-1/2 

of Sump Pump ~ " 



(g P nl) Maximum Equivalent Length of Vent, in Feet, (Given Below) 



10 


N.L. 2 


N.L. 


N.L. 


N.L. 


N.L. 


N.L. 


20 


270 


N.L. 


N.L. 


N.L. 


N.L. 


N.L. 


40 


72 


160 


N.L. 


N.L. 


N.L 


N.L. 


60 


31 


75 


270 


N.L. 


N.L. 


N.L. 


80 


16 


41 


150 


380 


NJL 


N.L 


100 


<10 3 


25 


97 


250 


N.L. 


N.L 


150 


NP 4 


<10 3 


44 


110 


370 


N.L. 


200 


NP 


NP 


20 


60 


210 


N.L. 


250 


NP 


NP 


10 


36 


132 


N.L. 


300 


NP 


NP 


<l(P 


22 


88 


380 


400 


NP 


NP 


NP 


<W 


44 


210 


500 


NP 


NP 


NP 


NP 


24 


130 



friction due to fittings, Changes in direction, and changes in diameter. Suggested 
allowances may be obtained from NBS Monograph 31 or other acceptable sources. 
An allowance of 50% of the developed length may be assumed if a more precise value 
is not available. 

2. No Limit; actual values greater than 500 feet. 

3. Less than 10 feet. 

4. Not permitted. 

12.14.3 Pneumatic Sewage Ejectors 

Pressure release vents for pneumatic sewage ejectors shall extend to a vent terminal that is separate from 
any gravity system vents. Such pressure release vents shall be of sufficient size to reduce the ejector tank to 
atmospheric pressure within 10 seconds, but shall be not less than 1-1/4" pipe size. 

12.15 SUDS PRESSURE VENTING 

12.15.1 ReliefVenting 

Where fixture or branch drains connect to a soil or waste stack within a suds pressure zone as described in Section 
11 . 11.2, a suds relief vent shall be provided for the fixture or branch drain. Suds relief vents shall be 2" minimum 
size but not less than one pipe size smaller than the drain branch that they serve. Such relief vents shall connect to 
the drain branch between the suds pressure zone and the first fixture trap on the branch. See Figure 12 15 1 



Comment: Suds pressure relief vents in Section 12.15 are larger than ordinary vents for drainage 
systems because the suds are heavier than air. Suds can weight from 2 to as much as 19 pounds per cubic 



2006 National Standard Plumbing Code-Illustrated 



303 



VENT 



BRANCH DRAIN FROM 
ONE OR MORE FIXTURES 



DRAINAGE STACK 



RELIEF VENT 
(Note 1) 




DRAIN CONNECTION IN A 
SUDS PRESSURE ZONE 



(Note 2) 



LEVEL OF SUDS PRESSURE ZONE 



SUDS PRESSURE 
ZONE 4 



NOTES: 

1 . Relief vents must be sized according to Table 12.15.1. 

2. Relief vents must not connect to a suds pressure zone in a vent stack 

Figure 12.15.1 
RELIEF VENTS FOR DRAIN CONNECTIONS IN A SUDS PRESSURE ZONE 



Drain Size 



V,i 

2 

3 
4 
5 
6 
8 



Table 12.15.1 
SUDS PRESSURE RELIEF VENTS 



Relief Vent Size 



12.15.2 Prohibited Vent Connections 

Connections shall not be made within the suds pressure zone of a vent stack that connects at or downstream 
from the base of a soil or waste stack, as described in Section 1 1.1 1.2.d. 

12.16 SIZE AND LENGTH OF VENTS 

12.16.1 Size of Fixture Vents 

a. Vents for individual fixtures shall be sized according to Table 12.16. 

b. Vents shall be not less than 1-1/4" size nor less than one-half the size of the fixture drain that they 
serve. 



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2006 National Standard Plumbing Code-Illustrated 



c. Where a vent pipe serves two or more fixtures, the size of the combined vent pipe shall be based on the 
sum of the drainage fixture units (DFU) for all of the drains served. 

d. Where the fixtures being vented are not connected to the same drain stack, the stack size used in Table 
12.16 shall be the equivalent stack size for their total combined DFU load, based on Table 1 1 .5. IB. 
EXCEPTION: As otherwise provided in this Code. 

See Figure 12.1 6. 1-A and-B 



Table 12.16 
SIZE AND LENGTH OF VENTS 



Size of 

drainage stack 

or fixture 

drain inches 


Drainage 
fixture 

units con- 
nected 


Diameter of Vent Required (Inches) 


1-1/4 


1-1/2 


2 


2-1/2 


3 


4 I 5 


6 


8 


Maximum Length of Vent (Feet) 






1-1/4 


1 


(1) 












1-1/2 


8 


50 j 150 






f§|f§§l§| 






Sfllil 


[ 2 


12 


30 


75 
50 
30 


200 










2 


20 


26 


150 














3 


10 




100 


100 


600 






- — - 




3 


30 




60 


200 


500 







3 


60 






50 80 


400 








4 


100 






35 100 


260 


1000 








4 


200 






30 


90 


250 


900 


1000 







4 


500 




i _ 


70 


180 


700 




5 


200 




j 


35 


80 


350 




.. 


5 


500 








30 


70 


300 


900 




5 


1100 








20 


50 


2200 


700 






6 


350 








25 


50 


200 


400 


1300 




6 


620 








" 


30 


125 


300 


1100 




6 


960 










24 


100 


250 


1000 




6 


1900 










20 


70 


200 


700 




8 


600 












50 


150 


500 


1300 


8 


1400 










40 


100 


400 


1200 


8 J 


2200 












30 


80 


250 


1100 


8 


3600 










- 


25 


60 


250 


800 


10 


1000 








liiitf': 




75 


125 


1000 


10 


2500 












50 


100 


500 


10 


3800 














30 


80 


350 


10 


5600 














25 


60 


250 



(1) The length of the vent is unlimited 



2006 National Standard Plumbing Code-IUustraled 



305 



lV t " MINIMUM- 




1K 2 " 



1>2 M MINIMUM 



WATER 
CLOSET 



3"- 




X 



NOTES: 

1 . Vent s for individual fixtures must be at least 1/2 of the size of the drain that they serve, but not less 
that 1-1/4" 

Figure 12.16.1 - A 
THE SIZE OF INDIVIDUAL FIXTURE VENTS 

V.T.R. 

J ! L 



OVERALL LENGTH OF LONGEST 
VENT PATH = 100 FEET 



PUBLIC 

TOILET ROOMS 

150 D.F.U. 



PUBLIC 

TOILET ROOMS 

150 D.F.U. 



4" 



EQUIVALENT DRAINAGE STACK = 5" (300 D.F.U.) 

NOTES: 

1 . Two groups of public toilet rooms are connected to a combined vent. 

2. The size of the vent for the 4" drain stack from each group with more than 1 00 DFU must be 3" if the 
overall length to the vent terminal is 100 feet. (Table 12.16). 

3. The size of an equivalent drainage stack with 300 DFU is 5" (Table 1 1 .5.1 B). 

4. The size of the combined vent for the 5" equivalent stack with 300 DFU and 100 feet is 4" in Table 
12.16 

Figure 12.16.1 - B 
THE SIZE OF VENTS FOR MULTIPLE FIXTURES ON DIFFERENT STACKS 

12.16.2 Size of Circuit or Loop Vents 

Circuit or loop vents shall be not less than one-half the size of the horizontal drainage branch that they serve. 
See Figure 12.16.2 



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2006 National Standard Plumbing Code-Illustrated 



RELIEF VENT 
(Note 4) 




VENT STACK 



CIRCUIT VENT 
(Note 3) 



NOTES: 



1. 

2. 
3. 
4. 



A lower floor is shown. It requires a relief vent because there are more than 4 water closets on the 

branch. 

The horizontal branch drain is 4" size 

The circuit vent must be 2" minimum size per Section 12.16.2. 

The relief vent must be 2" minimum size per Section 12.16.3. 

Figure 12.16.2 
THE SIZE OF CIRCUIT AND LOOP VENTS 

12.16.3 Size of Relief Vents 

a. The size of relief vents for circuit or loop vented branches of the drainage system shall be not less than 
one -half the size of the branch drain being served. 

b. Relief vents for stacks having ten or more branch intervals and relief vents for horizontal offsets in such 
stacks shall be the same size as the vent stack to which they connect. 

See Figure 12.16.2 

12.16.4 Size of Stack Vents and Vent Stacks 

The minimum required size of stack vents and vent stacks shall be in accordance with Table 12. 16. For the 
purpose of sizing, the length of a vent stack or stack vent shall be the developed length from its lowest 
connection with the drainage system to its termination in the open air, including any vent headers. 

12.16.5 Vent Headers 

a. Vent headers or portions thereof shall be sized according to Table 12.16. 

b. The number of fixture units (DFU) used to size vent headers shall be the sum of all fixture units (DFU) 
on all stacks served by each section of the header. 

c. The developed length of vent headers shall be the longest vent length from the vent connection at the 
base of the most distant stack to the vent terminal in the open air. 

d. The soil or waste stack size used to size vent headers shall be the equivalent size capable of handling 
the fixture unit load (DFU) on the vent header, based on Table 1 1 .5. IB. 



2006 National Standard Plumbing Code-Illustrated 



307 



12.16.6 Aggregate Size of Vent Terminals 

a. Each building sewer shall be vented by one or more vents extending from the drainage system, or 
branches thereof, to the open air above the roof. 

b. Stack vents and vent stacks shall be sized according to Table 12.16.4. 

c. The aggregate cross-sectional area of all vent terminals serving a sewer shall be not less than the cross- 
sectional area of the minimum required size of the building drain that they serve, at the point where it con- 
nects to the building sewer. (See Table 12.16.6 for the cross-sectional areas of pipes). 

EXCEPTION: The aggregate cross-sectional area requirement shall be exclusive of any requirements to 
prevent frost closure under Section 12.5. 

d. One or more vent terminals having the aggregate cross-sectional area of a 3 " vent terminal shall be permitted 
to vent a 4" building drain if the drainage fixture unit load (DFU) and number of bathroom groups served by the 
building drain does not exceed the maximum number allowed on a 3" building drain, as permitted by Section 
12.16.6.C 



Table 12.16.6 
NOMINAL PIPE CROSS SECTIONAL AREA (Sq. Inches) 



Nominal Pipe Size (ID) 



Cross Sectional Area (sq in.) 



I'm 

Vn 

2" 

2'n" 

3" 

4" 

5" 

6" 

8" 

10" 

12" 

15" 



1.2 

1.8 

3.1 

4.9 

7.1 

12.6 

19.6 

28.3 

50.3 

78.5 

113.1 

176.7 



12.16.7 Underground Vent Piping 

The minimum size of vent piping installed underground shall be 1-1/2". 

12.17 COMBINATION WASTE AND VENT SYSTEM 

12.17.1 Where Permitted 

a. A combination waste and vent system shall be permitted only where conditions preclude the installation 
of a conventionally vented drainage system as otherwise required by this Code. 

b. Combination waste and vent systems shall be limited to floor drains and other floor receptors, sinks, 
lavatories, and standpipes. 

12.17.2 Trap Size 

Traps in a combination waste and vent system shall be the normal size for the particular fixture. See Table 5.2. 

12.17.3 Trap Arms 

a. Fixtures shall be considered to be vented at the point that they connect to a combination waste and vent 
system. 

b. Where fixtures have conventionally sized trap arms, the maximum length of the trap arm from the weir 
of its trap to the point of connection to the combination waste and vent systems shall be as limited in Table 

12.8.1. 



308 



2006 National Standard Plumbing Code-illustrated 



c. In the case of fixtures with above-the-floor outlets, the vertical drop at the end of the trap arm shall 
be one size larger than the trap arm and be considered as the beginning of the combination waste and 
vent system. 

d. Floor-outlet fixtures shall also be permitted to drop into a vertical combination waste and vent that is 
at least one size larger than the trap arm. 

e. Where a fixture trap arm is sized as a combination waste and vent, its length shall not be limited and 
it shall be considered as a branch of the combination waste and vent system. 

f. The maximum vertical drop from a fixture trap arm to a horizontal drain below shall be 6 feet. 

12.17.4 Pipe Sizing 

The piping in a combination waste and vent system shall be sized according to Table 12.174 based on 
the number of drainage fixture units (DFU) served and the slope of the piping. 

EXCEPTION: No pipe shall be smaller than any section of piping upstream, including vertical drops from 
trap arms. 

Table 12.17.4 
PIPE SIZING FOR COMBINATION WASTE AND VENT SYSTEMS 



Load 


slope 
V," per ft 


slope 
V," per ft 


slope 
V per ft 


slope 
V 2 " per ft 


3 dm 


4" 


2" 


2" 


2" 


12 dfu 


4" 


s- 4 " 


3" 


3" 


20 dm 


1- 5" 


4" 


4" 


4" 


180 dm 


5" 


5" 


4" 


4" 


218dfu 


6" 


5" 


5" 


5" 


390 dm 


8" 


8" 


5" 


5" 


480 dfu 


8" 


8" 


6" 


6" 


700 dm 


8" 


8" 


6" 


6" 


840 dfu 


10" 


8" 


8" 


8" 


1600 dfu 


10" 


10" 


8" 


8" 


1920 dfu 


12" 


10" 


10" 


10" 



12.17.5 Maximum Slope 

All piping in a combination waste and vent system shall be horizontal and sloped at not greater than 1/2 
inch per foot. 

EXCEPTIONS: 

(1) Vertical drops at the end of trap arms. 

(2) Vertical drops of not greater than 45 degrees from horizontal where the vertical drop is not greater 
than 6 feet and the offset is at least 10 pipe diameters from any turn or branch connection. 

12.17.6 Branch Connections 

a. Connections to mains and branches within combination waste and vent systems shall be made 
horizontally at a slope not greater than 1 12 inch per foot. 

b. Branch connections shall not be made in vertical drops or offsets. 

12.17.7 Minimum Distances 

The distance between turns, offsets, and branch connections in combination waste and vent piping shall 
be not less than 10 pipe diameters. 



2006 National Standard Plumbing Code-Illustrated 



309 



12.17.8 Connections to Conventional Drainage Systems 

a. Combination waste and vent systems shall extend to the point of connection to a conventionally 
sized and conventionally vented drainage system. 

b. At the point of connection, the pipe size of the conventional system shall be at least as large as the 
combination system, and sized to accept the added drainage load from the combination system. 

c. Such connection from the combination system to the conventional system shall be made at an angle 
above horizontal of not less than 22-1/2 degrees nor more than 45 degrees. 

12.17.9 Connection of Individual Fixtures 

Where drains from individual fixtures are designed as a combination waste and vent and are connected to 
a conventional drainage system, the connection from the fixture to the conventional system shall be made 
according to Section 12.17.8. 

12.18 ISLAND SINK VENTING 

12.18.1 Where Permitted 

Island sink venting shall be permitted for sinks and lavatories where the ventpipe cannot rise 6 inches above 
the flood level rim of the fixture before turning horizontal. Kitchen sinks in dwelling units with dishwasher 
connections, food-waste-grinder connections, or both, shall be permitted to be i sland vented. Also see section 
12.8.1(3). 

12.18.2 Arrangement of Vent Piping; 

The island vent pipe shall rise vertically under the sink at the end of the fixture trap arm to at least 4 inches 
above the outlet of the fixture. The vent shall then turn downward and connect to the horizontal drain line 
below the floor downstream from the fixture drain connection so that the vertical vent drop will drain by gravity 
to the drainage system. A horizontal vent pipe shall be extended under the floor from the vertical vent drop 
to a point where it can rise vertically. The vertical rise at the end of the horizontal vent portion shall extend 
upward to at least 6 inches above the flood level rim of the fixture being vented before turning horizontal and 
connecting to a vent to the outdoors. The horizontal portion of the vent under the floor shall pitch back to the 
sink so that it will drain by gravity through the vertical vent drop connection to the drainage system. 

12.18.3 Size of Island Vent Pipes 

Island vent pipes shall be sized as individual or common vents in accordance with Section 12.16.1. 

12.18.4 Cleanouts Required 

Cleanouts shall be provided in the vertical vent drop under the sink and in the vertical rise beyond the 
horizontal portion of the vent so that any blockages in the vent piping can be rodded into the drainage system. 



12.19 OTHER DESIGNS 

Venting systems not described in this Code may be permitted by the Authority Having Jurisdiction if they 
provide the protection required by Section 12.2. 1 and are individually designed by a licensed professonal 
engineer. (See Appendix E - SPECIAL DESIGN PLUMBING SYSTEMS.) 



310 2006 National Standard Plumbing Code-Illustrated 






Wmm 






Jilllll 




Storm Water Drainage 



13.1 GENERAL 



13.1.1 WhereRequired 

Roofs, paved areas, yards, courts, and courtyards shall be drained to either a storm sewer where available, a 
combined sewer where necessary, or to a place of disposal satisfactory to the Authority Having Jurisdiction. 
EXCEPTION: Storm water from one- and two-family dwellings may be discharged on lawns or streets 
provided that the storm water flows away from the dwelling and does not otherwise create a nuisance. 

13.1.2 Storm Water Drainage to Sewer Prohibited 

Storm water shall not be drained into sewers intended for sewage only, except as approved by the Authority 
Having Jurisdiction. 



Comment #1: The peak storm water flows in combined sanitary and storm sewer systems can overload 
the sewage treatment facility, causing it to bypass untreated sewage into its point of discharge. 

Comment #2: In many cities with combined sewers, it is impractical to install separate sewers in the 
downtown areas because of the number of existing utilities under the streets. 

Comment #3: Some jurisdictions with combined sewers require that new or renovated buildings have 
separate sanitary and storm building drains so that they could be connected to separate sewers in the 
future. 



13.1.3 Sanitary and Storm Sewers 

Where separate systems of sanitaiy drainage and storm water are installed in the same property, the storm 
and sanitary building sewers and drains may be laid side by side in the same trench. 

13.1.4 Reserved 

13.1.5 Foundation Drains 

a. Foundation drains shall be provided around the perimeter of basements, cellars, crawl spaces or any 
building space below grade. The drains shall be positioned either inside or outside of the footings, and shall be 
of perforated or open-joint approved drain tile or pipe not less than 3" pipe size. The invert of foundation 
drains shall be not less than 2 inches below the underside of the floor slab being protected. 

b. Foundation drains shall be laid in a filter bed of gravel, crushed stone, slag, approved 3/4" crushed 
recycled glass aggregate, or other approved porous materials. The bottom of the filter bed shall be no higher 
than the bottom of the base course beneath the floor slab. There shall be not less than 2 inches of filter bed 



2006 National Standard Plumbing Code-Illustrated 



311 



beneath the foundation drain. Where foundation drains are located outside of the footings, there shall be at 
least 6 inches of filter bed above the top of the pipe. 

c. Drainage from foundations shall be discharged to a storm drain, street, alley, approved water course, or 
at grade. When discharged at grade, the point of discharge shall be at least 10 feet from any property line and 
shall not create a nuisance. 

d. Where foundation drains are below the required point of discharge, one or more automatic sump pumps 
shall be provided. The pump or pumps shall have adequate capacity to convey all drainage to its point of 
discharge. The minimum pump capacity shall be 1 5 gallons per minute at the required discharge head. Sump 
pits shall be sized to accommodate the pump(s), as recommended by the pump manufacturer, but shall be not 
less than 15 inches in diameter nor less than 18 inches deep. Sump pits shall be provided with fitted covers. 
Pits shall be located to avoid foot traffic where their covers do not have sufficient strength to carry such 
weight. Discharge lines from sump pumps shall be sized according to the design pump capacity and shall be 
not less than 1-1/4" pipe size. A check valve shall either be incorporated into each sump pump or be installed 
in the discharge line from each sump pump, except that check valves may be eliminated where the discharge 
pipe would be subject to freezing. Under such conditions the sump pit shall be adequately sized to prevent 
short cycling of the pump. 

e. Where sump pumps discharge at grade on unpaved surfaces, the discharge pipe shall extend to a splash 
block or equivalent, which shall be designed to contain the discharge, reduce its velocity, and avoid disturbing 
adjacent areas. Where necessary, the discharge pipe shall terminate with an elbow to direct the flow along 
the splash block. Splash blocks shall be at least 24 inches long. 

f. The water supply to water-operated storm water sump pumps shall be protected from backflow in 
accordance with Section 10.5. 

See Figures 13.1.5-A and-B 



FLOOR SLAB - 



!p25S-Bi5SSJJ5 



IRRbp 



GRADE (Note 3) 



FILTER BED (Note 2) 



'- ^ ^'j £*^ j 



J>i':t 
V '- 



Note 1 



■ FILTER BED (NOTE 2) 



■\V---y -X.fV«Vv/ ,--L,",X:- -.v.;-:". 






FOUNDATION DRAIN 
3" MINIMUM SIZE 



NOTES: 

1 . The invert of the foundation drain must be at least 2 inches below the underside of the floor slab. 

2. The filter bed must be at least 2" beneath the bottom of the drain pipe and at least 6" above the top 
of the pipe. Installing a filter fabric over the filter bed will keep fine soil particles from clogging the 
porous openings in the bed. 

3. Foundation drains require the same earth cover as drainage piping. 

Figure 13.1.5 - A 
A FOUNDATION DRAIN OUTSIDE OF A FOOTING 



312 



2006 National Standard Plumbing Code-Illustrated 



OUTLET OVER SPLASH BLOCK 
OR OTHER APPROVED 
POINT OF DISPOSAL 



NOTE1 



1 1/4" MINIMUM 



CHECK VALVE 




SUMP PUMP - PEDESTAL 
OR SUBMERSIBLE 



FITTED COVER 



FOUNDATION DRAIN 
SEE FIGURE 1 3.1. 5-A 



15" MINIMUM 

INSIDE 
DIAMETER 



NOTES: 

1 . Where subject to freezing weather, the discharge pipe should be sloped downward so that the outlet 
drains by gravity. 

Figure 13.1.5 - B 
A SUMP PUMP FOR FOUNDATION DRAINS 



2006 National Standard Plumbing Code-Illustrated 



313 



13.1.6 Areaway Drains 

a. Drainage shall be provided for open areaways below grade where storm water may accumulate. 
Areaways include outdoor spaces that provide access to basements or floor levels of a building that are below 
grade. Drains in such areas shall be sized according to Table 13.6.2 and shall include strainers as required for 
roof drains or floor drains. 

b. Areaway drains shall not connect to a foundation drain. 
EXCEPTION: Areaways not exceeding 100 square feet in area. 
See Figure 13.1.6 

AREA DRAIN 
AT BASE OF 
STAIRWELL 



FOUNDATION DRAIN 
(Notel) 




FOUNDATION DRAIN 
(Note 1) 



SUMP PUMP 
(WHERE REQUIRED) 



NOTES: 

1. The foundation drains can be inside or outside of the footings. See Figures 13.1.5- A and 13.1.5- 
B. 

2. The areaway drain can connect to a foundation drain if the size of the areaway (and any adjacent 
areas that drain into the areaway) is 1 00 square feet or less. It must discharge separately if the 
area being drained is larger than 1 00 square feet. 

3. Drain pipes for areaways must be sized according to Table 1 3.6.2, based on the rainfall rate and the 
size of the areaway and any adjacent areas that may drain into the areaway. The minimum drain 
pipe sizes are 2" if sloped 1/4 in./ft or more and 3" if sloped 1/8 in./ft. 

Figure 13.1.6 
THE ARRANGEMENT OF AN AREAWAY DRAIN 



13.1.7 Window Well Drains 

Window wells shall be drained as required for areaways, except that window wells not greater than 10 
square feet in area shall be permitted to drain into a foundation drain, either directly by means of a 2" mini- 
mum size drain, or indirectly through a porous filter bed. See Figures 13. 1.7- A and-B 



314 



2006 National Standard Plumbing Code-Illustrated 



AREA DRAIN 



WINDOW WELL 
DRAIN PIPE 
(Notes 2 & 3) 



PIPED DIRECTLY TO THE SUMP IF 
WINDOW WELL EXCEEDS 10 SQ. FT. 




FOUNDATION DRAIN 
(Note 1) 



NOTES: 



1. 



2. 



The foundation drains can be inside or outside of the footings. See Figures 1 3. 1 .5 - A and 

The window well drain can connect to a foundation drain if the size of the window well (and any 
adjacent areas that drain into the window well) is 10 square feet or less. It must discharge sepa- 
rately if the area being drained is larger than 1 square feet 

Drain pipes for window wells must be sized according to Table 13.6.2, accounting for the rainfall rate 
and the size of the window well and any adjacent areas that may drain into the window well The 
minimum drain pipe sizes are 2" if sloped 1/4 in./ft or more and 3" if sloped 1/8 in./ft. 

Figure 13.1.7 - A 
A WINDOW WELL DIRECTLY DRAINED 



AREA DRAIN - 
OR GRAVEL 
BASE 



POROUS FILTER 
BED (NOTE 2) -_ 



WINDOW 
WELL 



Jt 



FOUNDATION DRAIN - 
(NOTE 1) 







2. 



NOTES: 

1. The foundation drain must be outside of the footings. See Figure 13 1 5-B 

The porous filter bed must extend from the area drain in the window well to the foundation drain 
Installing a filter fabric between the earth and the filter bed will keep the porous bed from becoming 
clogged with fine soil particles. y 

Figure 13.1.7 - B 
A WINDOW WELL INDIRECTLY DRAINED 



2006 Manorial Standard Plumbing Code-Illustrated 



315 



13.1.8 Parking and Service Garages 

Storm water drainage from parking and service garages shall be in accordance with Sections 6.3.1.d and 
6.3. I.e. 

13.1.9 Reserved 

13.1.10 RoofDrainage 

13.1.10.1 Primary RoofDrainage 

Roof areas of a building shall be drained by roof drains or gutters. The location and sizing of drains and 
gutters shall be coordinated with the structural design and pitch of the roof. Unless otherwise required 
by the Authority Having Jurisdiction, roof drains, gutters, vertical conductors or leaders, and horizontal 
storm drains for primary drainage shall be sized based on a storm of 60 minutes duration and 100-year 
return period. (See Appendix A) 

13.1.10.2 Secondary RoofDrainage 

a. Where parapet walls or other construction extend above the roof and create areas where storm 
water would become trapped if the primary roof drainage system failed to provide sufficient drainage, 
an independent secondary roof drainage system consisting of scuppers, standpipes, or roof drains shall 
be provided. Secondary roof drainage shall be sized for a 100-year, 15 -minute storm (see Appendix 
A). The capacity of the primary system shall not be considered in the sizing of the secondary system. 

b. Where secondary drainage is provided by means of roof drains or standpipes, the secondary 
system shall be separate from the primary system and shall discharge independently at grade or other 
approved point of discharge. 

c. Where secondary roof drainage is provided, the overflow level(s) into the secondary system shall 
be established by the amount of ponding that is allowed in the structural design of the roof, including 
roof deflection. An allowance shall be made to account for the required overflow head of water above 
the secondary inlets. The elevation of the secondary inlet plus the required overflow head shall not 
exceed the maximum allowable water level on the roof. 

d. Scuppers shall be sized as rectangular weirs, using hydraulic principles to determine the required 
length and resulting overflow head (see Appendix A). Secondary roof drains and standpipes shall be 
sized according to Table 13.6.1 Where standpipes are used, the head allowance required under 
Section 13.1.10.2(3) shall be not less than 1-1/2 inches. 

e. Strainers shall not be required on open standpipes when used for secondary inlets. 

f. Where secondary roof drainage is provided by roof drains or standpipes, they shall be permitted to 
discharge horizontally, similar to scuppers, but below the roof level. 

13.1.10.3 VerticalWalls 

Where vertical walls drain onto roofs, an allowance based on 50% of the maximum projected wall area 
shall be added to the roof area onto which each wall drains. 

13.1.10.4 Equivalent Systems 

When approved by the Authority Having Jurisdiction, the requirements of Sections 13.1.10.1 and 
13.1.10.2 shall not preclude the installation of an engineered roof drainage system that has sufficient 
capacity to prevent water from ponding on the roof in excess of that allowed in the roof structural 
design during a 100-year, 15-minute storm. 



3 J6 2006 National Standard Plumbing Code-Illustrated 



13.1.11 Continuous Flow 

Where continuous flow from a spring or ground water is encountered in a foundation drainage system or 
other subsoil drain, the discharge shall be piped to a storm sewer or approved water course. 

13.1.12 Backwater Valves 

Where foundation drains, areaway drains, window well drains, or other storm water drains discharge by 
gravity and are subject to backflow from their point of discharge, a backwater valve shall be provided in the 
discharge line. Backwater valves shall comply with the requirements of Section 5.5. 

13.2 MATERIALS 

See Section 3.7. See Table 3.7 for approved materials for storm water drainage. 

13.3 TRAPS IN STORM DRAINAGE SYSTEMS 

13.3.1 General 

a. Traps shall be installed in a storm drainage system if it connects to a combined sewer conveying both 
sewage and storm water. 

EXCEPTION: Traps shall not be required where roof drains, rain leaders, and other inlets are at locations 
allowed under Section 12.4.4 for vent terminals. 

b. Floor drains or other receptors within a building shall be individually trapped if they are connected to a 
storm drainage system, regardless of whether or not the sewer is combined. 

c. Traps required under this section shall comply with the requirements of Section 5.3.1, 5.3.2, 5.3.3, 5.3.5 
and 13.3.2. Traps shall have accessible cleanouts or other means of clearing the trap. 



Comment: Floor drains or other receptors that are connected to a storm drainage system or combined 
sewer and are subject to evaporation of the trap seal must be provided with a deep seal trap or other 
means of maintaining the trap seal. See Section 5.3.6. 



13.3.2 Location of Traps 

Where traps are required under Section 13.3. l.a, they shall be installed either on individual branches of the 
storm drainage system or in the building storm drain or building storm sewer before it connects to the com- 
bined sewer. Traps shall not be installed in locations where they will be subject to freezing. Where traps are 
required for rain leaders, the minimum earth cover shall be as required in Section 2.16.b. See Figure 13.3.2 



2006 National Standard Plumbing Code-Illustrated 317 



STORMWATER 
CONDUCTORS 



STORMWATER 
CONDUCTORS 



SOIL STACK 




TRAP WITH CLEANOUTS 



"AT LEAST 10' 
FROM SOIL STACK 
(NOTE 1) 



BUILDING STORM DRAIN 



COMBINED BUILDING DRAIN 



WYE FITTING - 
(NOTE 2) 

TO COMBINED BUILDING SEWER 

NOTES: 

1 . The trap is required when any of the storm water inlets are at locations where sanitary vent termi- 
nals would not be permitted in Section 12.4.4. If all storm water inlets are at locations where 
sanitary vent terminals would be permitted, the trap is not required. The storm water inlets will be 
the same as vent terminals for the sanitary drainage system. Only those inlets in prohibited loca- 
tions for sanitary vent terminals need to be trapped. 

2. The connection between the building storm drain and the building sanitary drain needs to be a 
horizontal wye fitting that is at least 10 feet downstream from any soil stack. 



Figure 13.3.2 

A TRAP IN A STORM DRAINAGE SYSTEM 

CONNECTED TO A COMBINED SEWER 

13.3.3 Size of Traps 

Traps shall be the same size as the drain pipe in which they are installed. 

13.4 LEADERS OR CONDUCTORS AND CONNECTIONS 

13.4.1 Not to be Used Improperly 

Leaders or conductors shall not be used as soil, waste, or vent pipes nor shall soil, waste, or vent pipes be 
used as leaders. 

13.4.2 Protection of Rain Water Leaders 

Rain water leaders installed along alleyways, driveways, or other locations where they may be exposed to 
damage shall be protected by metal guards, shall be recessed into the wall, or shall be constructed from 
ferrous alloy pipe to a point 5 foot above grade. See Figure 13.4.2 



Comment #1: The "10 feet downstream " requirement allows the sanitary discharge to stabilize before 
mixing with the storm water flow. It also reduces the backpressure on the sanitary drainage system that 
may be caused by heavy storm water discharges. 

Comment #2: The horizontal wye connection between the two drainage systems permits the flows to mix 
more uniformly without blocking the drain. 



318 



2006 National Standard Plumbing Code-illustrated 



LEADERS 




METAL 

GUARD 



RECESS IN 

BUILDING 

WALL 



PLASTIC OR 
SHEET METAL 
LEADER 

GALVANIZED STEEL 
OR CAST IRON 
DOWNSPOUT BOOT 



DRIVEWAY 



Figure 13.4.2 
PROTECTION OF RAIN WATER LEADERS 



13.4.3 Combining Storm with Sanitary Drainage 

The sanitary and storm drainage system of a building shall be entirely separate, except that where a combined 
sewer is used, the building storm drain shall be connected in the same horizontal plane through a single wye 
fitting to the combined sewer at least 10 feet downstream from any soil stack. 

13.4.4 Double Connections of Storm Drains 

Where the sanitary and storm drains are connected on both sides of the combined sewer, single wyes shall 
be used and the requirements of Section 1 3.4.3 relative to the location of connections shall also apply. See 
Figure 1.2.15 



Comment: Double pattern wye fittings are not permitted to connect sanitary drains and storm drains to a 
combined drain. This is to prevent a heavy flow in one drain branch from causing a backpressure in the 
other drain branch. 



13.5 ROOF DRAINS 



13.5.1 Compliance and Materials 

Roof drains shall comply with ASME Al 12.6.4 and be constructed of coated or galvanized cast iron, bronze, 
stainless steel, plastic, or other corrosion-resisting materials. Drains shall include any deck clamps or other 
appurtenances necessaiy for installation and coordination with the roofing system. 

13.5.2 Dome Strainers 

Roof areas shall be drained to roof drains having raised dome strainers with dome free areas complying with 
ASME A 1 1 2 .6.4. The minimum free dome area shall be one and one-half ( 1-1/2) times the area of the drain outlet 
connection. 
EXCEPTIONS 

(1) Pitched roofs draining to hanging gutters. 

(2) Roof areas subject to pedestrian and/or vehicular traffic. 



2006 National Standard Plumbing Code-Illustrated 



319 



13.5.3 Flat Grates 

Roof drains on patios, sun decks, parking decks, and other areas subject to pedestrian and/or vehicular traffic shall 
have flat grates with a free inlet area complying with ASME 1 12.6.4. The minimum grate free area shall be two 
times the cross-sectional area of the drain outlet. Such drains shall not be located where they cannot be readily 
inspected and maintained on a regular basis. 

13.5.4 Roof Drain Flashings 

The connection between roofs and roof drains that pass through the roof and into the interior of the building 
shall be made watertight by the use of proper flashing material. 

13.5.5 Roof Drain Restrictions 

The roof drain size shall not be restricted by insertion of any roofing material or other objects to insure water 
flow into the drain. 

13.5.6 Roof Drain Outlet Pipe Size 

The outlet pipe size of roof drains having vertical conductors shall be not less than the size required for 
vertical conductors in Table 13.6. 1 . 

13.6 SIZE OF LEADERS, GUTTERS AND STORM DRAIN PIPING 

13.6.1 Vertical Conductors and Leaders 

Vertical storm water conductors and leaders shall be sized according to Table 13.6.1. Where a vertical pipe 
section is smaller than the preceding horizontal pipe section, the reduction in size shall be made in the vertical 
pipe section. 

13.6.2 Size of Horizontal Storm Drain Piping 

Horizontal storm drain piping shall be sized according to Table 13.6.2. Such piping includes horizontal offsets 
in storm water conductors, building drains, building sewers, and branches thereof. The size of the horizontal 
drain piping shall not be reduced in the direction of flow. 

13.6.3 Size of Roof Gutters 

The size of semicircular roof gutters shall be based on the maximum projected roof area, according to Table 
13.6.3. 

13.7 RESERVED 

13.8 SIZING FOR CONTINUOUS OR INTERMITTENT FLOWS 

Continuous or intermittent flows from a sump pump, air conditioning condensate drain, or other approved discharge 
into a storm drainage system shall be determined in gallons per minute flow. Air conditioning condensate drainage 
shall be based on not less than 0.006 gpm/ton. Such flows shall be added to the stormwater load on the storm 
drainage system, which shall also be determined on the basis of gallons per minute according to Table A.l and 
Section A. 3 in Appendix A. 



320 2006 National Standard Plumbing Code-Illustrated 



Table 13.6.1 
SIZE OF VERTICAL CONDUCTORS AND LEADERS 


Nominal 

Diameter 

(inches) 


Flow 

Capacity 

(GPM) 


Allowable Projected Roof Area 
at Various Rates of Rainfall per Hour (Sq. Ft.) 


1" 


2" 


3" 


4" 


5" 


6" 


2" 


23 


2,180 


1,090 


727 


545 


436 


363 


3" 


67 


6,426 


3,213 


2,142 


1,607 


1,285 


1,071 


4" 


144 


13,840 


6,920 


4,613 


3,460 


2,768 


2,307 


5" 


261 


25,094 


12,547 


8,365 


6,273 


5,019 


4,182 


6" 


424 


40,805 


20,402 


13,602 


10,201 


8,161 


6,801 


8" 


913 


87,878 


43,939 


29,293 


21,970 


17,576 


14,646 


10" 


1655 


159,334 


79,667 


53,111 


39,834 


31,867 


26,556 


12" 


2692 


259,095 


129,548 


86,365 


64,774 


51,819 


43,183 


15" 


4880 


469,771 


234,886 


156,590 


117,443 


93,954 


78,295 






7" 


8" 


9" 


10" 


11" 


12" 


2" 


23 


311 


272 


242 


218 


198 


182 


3" 


67 


918 


803 


714 


643 


584 


536 


4" 


144 


1,977 


1,730 


1,538 


1,384 


1,258 


1,153 


5" 


261 


3,585 


3,137 


2,788 


2,509 


2,281 


2,091 


6" 


424 


5,829 


5,101 


4,534 


4,080 


3,710 


3,400 


8" 


913 


12,554 


10,985 


9,764 


8,788 


7,989 


7,323 


10" 


1655 


22,762 


19,917 


17,704 


15,933 


14,485 


13,277 


12" 


2692 


37,014 


32,387 


28,788 


25,910 


23,554 


21,591 


15" 


4880 


67,110 


58,721 


52,197 


46,977 


42,706 


39,146 



NOTES: 

1 . Flow capacities are based on stacks flowing 7/24 full. 

2. Interpolation between rainfall rates is permitted. 

13.9 CONTROLLED FLOW STORM WATER SYSTEM 

13.9.1 Application 

In lieu of sizing the storm drainage system on the basis of actual maximum projected roof areas as previously 
described in this Chapter, the roof drainage system, or part thereof may be sized on equivalent or adjusted 
maximum projected roof areas that result from controlled flow and storage of storm water on the roof pro- 
vided flow control devices are used and subject to the approval of the Authority Having Jurisdiction. 

13.9.2 Design 

A controlled flow storm water system shall be designed, installed, inspected and certified as an engineered 
special design plumbing system as outlined in Appendix E of this Code. 



2006 National Standard Plumbing Code-Illustrated 



321 



Table 13.6.2 Part 1 
SIZE OFHORIZONTAL STORMDRAINS (for 1 "/hrto 67hrrainfallrates) 



Size of 

Drain 

(inches) 


Design Flow 

of Drain 

(GPM) 


Allowable Projected Roof Area at Various 
Rates of Rainfall per Hour (Square Feet) 


l'Vhr 


2"/hr 


37hr 


4"/hr 


57hr 


67hr 


Slope 1/16 inch/foot 


2 
















3 
















4 


53 


5,101 


2,551 


1,700 


1,275 


1,020 


850 


5 


97 


9,336 


4,668 


3,112 


2,334 


1,867 


1,556 


6 


157 


15,111 


7,556 


5,037 


3,778 


3,022 


2,519 


8 


339 


32,629 


16,314 


10,876 


8,157 


6,526 


5,438 


10 


615 


59,194 


29,597 


19,731 


14,798 


11,839 


9,866 


12 


999 


96,154 


48,077 


32,051 


24,039 


19,231 


16,026 


15 


1812 


174,405 


87,203 


58,135 


43,601 


34,881 


29,068 


















Size 


GPM 


l'Vhr 


2"/hr 


3"/hr 


4"/hr 


57hr 


6"/hr 


Slope 1/8 inch/foot 


2 
















3 


35 


3,369 


1,684 


1,123 


842 


674 


561 


4 


75 


7,219 


3,609 


2,406 


1,805 


1,444 


1,203 


5 


137 


13,186 


6,593 


4,395 


3,297 


2,637 


2,198 


6 


223 


21,464 


10,732 


7,155 


5,366 


4,293 


3,577 


8 


479 


46,104 


23,052 


15,368 


11,526 


9,221 


7,684 


10 


869 


83,641 


41,821 


27,880 


20,910 


16,728 


13,940 


12 


1413 


136,002 


68,001 


45,334 


34,000 


27,200 


22,667 


15 


2563 


246,689 


123,345 


82,230 


61,672 


49,338 


41,115 


















Size 


GPM 


l'Vhr 


2"/hr 


3"/hr 


4"/hr 


5"/hr 


6"/hr 


Slope 1/4 inch/foot 


2 


17 


1,636 


818 


545 


409 


327 


273 


3 


50 


4,813 


2,406 


1,604 


1,203 


963 


802 


4 


107 


10,299 


5,149 


3,433 


2,575 


2,060 


1,716 


5 


194 


18,673 


9,336 


6,224 


4,668 


3,735 


3,112 


6 


315 


30,319 


15,159 


10,106 


7,580 


6,064 


5,053 


8 


678 


65,258 


32,629 


21,753 


16,314 


13,052 


10,876 


10 


1229 


118,292 


59,146 


39,431 


29,573 


23,658 


19,715 


12 


1999 


192,404 


96,202 


64,135 


48,101 


38,481 


32,067 


15 


3625 


348,907 


174,454 


116,302 


87,227 


69,781 


58,151 


















Size 


GPM 


l'Vhr 


2"/hr 


3"/hr 


4"/hr 


5"/hr 


67hr 


Slope 1/2 inch/foot 


2 


24 


2,310 


1,155 


770 


578 


462 


385 


3 


70 


6,738 


3,369 


2,246 


1,684 


1,348 


1,123 


4 


151 


14,534 


7,267 


4,845 


3,633 


2,907 


2,422 


5 


274 


26,373 


13,186 


8,791 


6,593 


5,275 


4,395 


6 


445 


42,831 


21,416 


14,277 


10,708 


8,566 


7,139 


8 


959 


92,304 


46,152 


30,768 


23,076 


18,461 


15,384 


10 


1738 


167,283 


83,641 


55,761 


41,821 


33,457 


27,880 


12 


2827 


272,099 


136,050 


90,700 


68,025 


54,420 


45,350 


15 


5126 


493,379 


246,689 


164,460 


123,345 


98,676 


82,230 



322 



2006 National Standard Plumbing Code— Illustrated 



NOTES: 

1 . Design flows in Table 13.6.2 Part 1 are based on fairly rough pipe with a Manning friction coefficient "n" = 
0.015. 

2. The Authority Having Jurisdiction should be consulted for the rainfall rate to be used for a particular location. 



Table 13.6.2 Part 2 
SIZE OF HORIZONTAL STORM DRAINS (for 7"/hr to 12"/hrrainfall rates) 



Size of Drain 
(inches) 


Design Flow 
of Drain 


Allowable Projected Roof Area at Various Rates of Rainfall per Hour 
(Square Feet of Root) 


Slope 1/16 inch/foot 


Size 


(GPM) 


7"/hr 


87hr 


97hr 


lO'Vhr 


ll'Vhr 


127hr 


2 
















3 
















4 


53 


729 


638 


567 


510 


464 


425 


5 


97 


1,334 


1,167 


1,037 


934 


849 


778 


6 


157 


2,159 


1,889 


1,679 


1,511 


1,374 


1,259 


8 


339 


4,661 


4,079 


3,625 


3,263 


2,966 


2,719 


10 


615 


8,456 


7,399 


6,577 


5,919 


5,381 


4,933 


12 


999 


13,736 


12,019 


10,684 


9,615 


8,741 


8,013 


15 


1812 


24,915 


21,801 


19,378 


17,441 


15,855 


14,534 


Slope 1/8 inch/foot 


Size 


GPM 


77hr 


8"/hr 


9"/hr 


10'Vhr 


ll'Vhr 


127hr 


2 
















3 


35 


481 


421 


374 


337 


306 


281 


4 


75 


1,031 


902 


802 


722 


656 


602 


6 


223 


3,066 


2,683 


2,385 


2,146 


1,951 


1,789 


8 


479 


6,586 


5,763 


5,123 


4,610 


4,191 


3,842 


10 


869 


11,494 


10,455 


9,293 


8,364 


7,604 


6,970 


12 


1413 


12,429 


17,000 


15,111 


13,600 


12,364 


11,334 


15 


2563 


35,241 


30,836 


27,410 


24,669 


22,426 


20,557 


Slope 1/4 inch/foot 


Size 


GPM 


7"/hr 


8"/hr 


97hr 


lO'Vhr 


ll'Thr 


12"/hr 


2 


17 


234 


205 


182 


164 


149 


136 


3 


50 


688 


602 


535 


481 


438 


401 


4 


107 


1,471 


1,287 


1,144 


1,030 


936 


858 


5 


194 


2,668 


2,334 


2,075 


1,867 


1,698 


1,556 


I 6 


315 


4,331 


3,790 


3,369 


3,032 


2,756 


2,527 


8 


678 


9,323 


8,157 


7,251 


6,526 


5,933 


5,438 


10 


1229 


16,899 


14,787 


13,144 


11,829 


10,754 


9,858 


12 


1999 


27,486 


24,051 


21,378 


19,240 


17,491 


16,034 


15 


3625 


49,844 


43,613 


38,767 


34,891 


31,719 


29,076 



2006 National Standard Plumbing Code-Illustrated 



323 



Table 13.6.2 Part 2 (continued) 
SIZE OF HORIZONTAL STORM DRAINS (for 7"/hr to 1 2"/hr rainfall rates) 



Slope 1/2 inch/foot 


Size 


GPM 


77hr 


8"/hr 


9"/hr 


10"/hr 


ll'Vhr 


127hr 


2 


24 


330 


289 


257 


231 


210 


193 


3 


70 


963 


842 


749 


674 


613 


562 


4 


151 


2,076 


1,817 


1,615 


1,453 


1,321 


1,211 


5 


274 


3,768 


3,297 


2,930 


2,637 


2,398 


2,198 


6 


445 


6,119 


5,354 


4,759 


4,283 


3,894 


3,569 


8 


959 


13,186 


11,538 


10,256 


9,230 


8,391 


7,692 


10 


1738 


23,898 


20,910 


18,587 


16,728 


15,208 


13,940 


12 


2827 


38,871 


34,012 


30,233 


27,210 


24,736 


22,675 


15 


5126 


70,483 


61,672 


54,820 


49,338 


44,835 


41,115 



NOTES: 

1. Design flows in Table 13.6.2 Part 1 are based on fairly rough pipe with a Manning friction coefficient 
"n" = 0.015. 

2. The Authority Having Jurisdiction should be consulted for the rainfall rate to be used for a particular location. 



Table 13.6.3 
SIZE OF ROOF GUTTERS' 



Diameter of 

Gutter 2 

Inches 



Maximum Projected Roof Area for Gutters 

Vlfi in Slope 3 

Sq. Ft. GPM 



3 

4 
5 
6 
7 
8 
10 



170 

360 

625 

960 

1,380 

1,990 

3,600 



7 
15 
26 
40 
57 
83 
150 



1. Table 13.6.3 is based upon a maximum rate of rainfall of 4 inches per hour. Where 
maximum rates are more or less than 4 inches per hour, the figures for drainage area shall 
be adjusted by multiplying by 4 and dividing by the local rate in inches per hour. See 
Appendix A. 

2. Gutters other than semicircular may be used provided they have an equivalent cross- 
sectional area. 

3 . Capacities given for slope of 1 / 1 6 inch per foot shall be used when designing for greater 
slopes. 



324 



2006 National Standard Plumbing Code-Illustrated 



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Special Requirements For Health Care Facilities 



14.1 GENERAL 

This Chapter applies to special fixtures and systems that occur in health care facilities and to the special plumbing 
requirements in such facilities. Ordinary plumbing in such facilities shall comply with the other applicable Chapters 
of this Code. * F 

14.2 WATER SERVICE 

Where required by the Authority Having Jurisdiction, hospitals and similar health care facilities shall have dual 
water service lines to maintain a water supply in the event of a water main failure. Where possible, the service 
pipelines shall be connected to different water mains so that a single water main break can be isolated and re- 
paired without shutting off all water service to the facility. 

14.3 MEDICAL GAS AND VACUUM PIPING SYSTEMS 

14.3.1 General 

The installation of medical gas and vacuum piping systems shall be in accordance with the requirements of 
either NFPA 99 - Standard for Health Care Facilities or NFPA 99C - Gas and Vacuum Systems. 

14.3.2 Professional Qualifications of Installers, Inspectors and Verifiers 

Installers (including brazers), inspectors, and verifiers of medical gas and vacuum systems shall meet the 
requirements of ANSI/ASSE Series 6000 - Professional Qualification Standard for Medical Gas Systems 
Installers, Inspectors, and Verifiers, or the equivalent. 

14.4 PROTRUSIONS FROM WALLS 

Drinking fountains, control valves, medical gas station outlets, vacuum inlet stations, risers, cleanout covers and 
other devices shall be fully-recessed in corridors and other areas where patients may be transported on a gurney 
hospital bed, or wheelchair. Protective guards shall be provided where necessary. 

14.5 MENTAL PATIENT ROOMS 

Piping and drain traps in mental patient rooms shall be concealed. Fixtures and fittings shall be vandal-proof. 



Comment: Plumbing that is accessible to mental patients must be suicide-proof, vandal-proof, and 
sound-proof Piping is installed in chases that are not accessible to the patients. Special fixtures, such 
as combination lavatory/toilets, are available for such applications. The fixtures are pushbutton 
operated to avoid faucet handles. Most fixtures are constructed of stainless steel. The plumbing fixtures 
used in mental facilities are similar to those used in correctional institutions. 



2006 National Standard Plumbing Code-Illustrated 32 c 



14.6 PROHIBITED LOCATIONS FOR ICE STORAGE 

Ice makers or ice storage chests shall not be located in a Soiled Utility Room or similar areas where subject to 
possible contamination. 

14.7 CROSS CONNECTION CONTROL AND BACKFLOW PREVENTION 

a. Backflow prevention shall be in accordance with Section 10.5. 

b. Vacuum breakers for bedpan washers shall be not less than 5 feet above the floor. 

14.8 CLINICAL SINKS AND BEDPAN WASHERS 

14.8.1 General 

a. Clinical sinks and bedpan washers, and flushing-rim service sinks shall be installed in the same manner 
as water closets. Where such fixtures have a vent connection on the inlet side of their trap, a local vent shall 
be provided in accordance with Section 14.9. 

b. Clinical sinks shall not be used as a substitute for non-flushing service sink, nor shall a non-flushing 
service sink be utilized to clean bedpans. 

c. Vacuum breakers for bedpan washers shall be installed in accordance with Section 14.7.b. 
See Figure 14.8 



326 2006 National Standard Plumbing Code-Illustrated 



VACUUM BREAKER 



MIXING VALVE 



FLUSH VALVE 



WATER CLOSET - 




- WALL HUNG 
BEDPAN WASHER 



-HAND SPRAY WITH 
VOLUME CONTROL 



WALL CONTROL TYPE 



SINK FAUCET 



FLUSH VALVE 



WATER CLOSET OR - 
SERVICE SINK WITH 
FLUSHING RIM 
(CLINICAL SINK) 




VACUUM BREAKER 



FLUSH VALVE 



HOSE AND 
SPRAY NOZZLE 



FOOT VALVE 

CONTROL 




WATER CLOSET OR 
SERVICE SINK WITH 
FLUSHING RIM 
(CLINICAL SINK) 



FOOT CONTROL TYPE 



DIVERTER TYPE 



NOTES: 

1 . The divertor type of bedpan washer is typically installed in a patient toilet room. When the divertor 
is fully raised, the flush valve supplies the water closet bowl in the normal manner. When the 
divertor is lowered, the flush valve supplies the divertorto rinse the bedpan. After the bedpan has 
been rinsed into the water closet, the divertor can be raised and the water closet flushed. The 
elevation of the flush valve vacuum breaker above the overflow rim level of the water closet should be 
as recommended by the manufacturer. 

2. The wall control type of bedpan washer is typically installed in a patient toilet room. The bedpan is 
rinsed into the water closet bowl using the hand spray from the wall control unit. The water closet is 
then flushed using the flush valve. Section 14.7.b requires that the vacuum breaker in the wall 
control unit be at least 5 feet above the floor to prevent a cross connection. 

3. The foot control type of bedpan washer is typically installed in a soiled utility room with a clinical 
sink. The bedpan is rinsed into the water closet bowl using the hand spray and foot control valve. 
The clinical sink is then flushed using the flush valve. Section 14. 7. b requires that the vacuum 
breaker for the hose spray be at least 5 feet above the floor to prevent a cross connection. The sink 
faucet allows the clinical sink to be used as a service sink for housekeeping purposes. 

Figure 14.8 
TYPES OF BEDPAN WASHERS 



2006 National Standard Plumbing Code-Illustrated 



327 



14.9 LOCAL VENTS AND STACKS FOR CLINICAL SINKS 
OR BEDPAN WASHERS 

14.9.1 General 

Where clinical sinks or bedpan washers have provisions for a local vent, a local vent shall be extended to the 
outdoors above the roof. Local vents shall terminate in accordance with Section 12.4. Local vents from 
clinical sinks or bedpan washers shall not be connected to vapor vents for sterilizers or to any drainage 
system vent. 

14.9.2 Material 

Local vent piping shall be of a material acceptable for sanitary vents in accordance with Section 3.6. 

14.9.3 Required Size and Arrangement 

A local vent serving a single clinical sink or bedpan washer shall be not less than 2" pipe size. Where such 
fixtures are installed back-to-back or are located above each other on more than one floor, a local vent stack 
may be provided to serve multiple fixtures. A 2" local vent stack may serve up to three fixtures. A 3" local 
vent stack may serve up to six fixtures. A 4" local vent stack may serve up to twelve fixtures. In multiple 
installations, the connections to the local vent stack shall be made using sanitary tee or tee-wye fittings 
oriented for upward flow from the branch. A branch connection to a local vent stack shall extend not more 
than 5 feet horizontally and shall be sloped not less than 1/4 inch per foot back towards the fixture served. 

14.9.4 Provisions for Drainage 

Provisions shall be made for the drainage of vapor condensation within local vent piping. A local vent serving 
a single fixture may drain back to the fixture served. The base of a local vent stack serving one or more 
fixtures shall be directly connected to a trapped and vented waste branch of the sanitary drainage system. 
The trap and waste branch shall be the same size as the local vent stack. The trap seal depth shall be not less 
than 3 inches. The vent for the waste branch shall be 1-1/4" minimum size, but not less than one-half the size 
of the waste branch. 

14.9.5 Trap Priming 

The waste trap required under Section 14.9.4 shall be primed by at least one clinical sink or bedpan washer 
on each floor served by the local vent stack. A priming line not less than 1/4" OD size shall be extended from 
the discharge or fixture-side of the vacuum breaker protecting the fixture water supply to the local vent stack. 
A trap having not less than a 3-inch water seal shall be provided in the priming line. The line shall prime the 
trap at the base of the local vent stack each time that a fixture is flushed. 

14.10 STERILIZERS 

14.10.1 General 

The requirements of this Section apply to sterilizers and bedpan steamers. Such equipment shall be installed in 
accordance with this Code and the manufacturer's instructions. 

14.10.2 Indirect Waste Connections 

All waste drainage from sterilizers and bedpan steamers shall be indirectly connected to the sanitary drainage 
system through an air gap, in accordance with Chapter 9. Indirect waste pipes shall be not less than the size 
of the drain connection on the fixture. Separate waste pipes shall be provided for each fixture, except that up 



2006 National Standard Plumbing Code-Illustrated 



to three sterilizers may have a common indirect waste pipe if its developed length does not exceed 8 feet. The 
size of such common indirect waste pipes shall be not less than the aggregate cross-sectional area of the 
individual sterilizer drain connections. Except for bedpan steamers, indirect waste pipes shall not require traps. 

14.10.3 FloorDrains 

a. A trapped and vented floor drain, not less than 3" pipe size, shall be provided in each recess room or 
space where recessed or concealed portions of sterilizers are located. The floor drain shall drain the entire 
floor area and shall receive the indirect waste from at least one sterilizer. Where an air gap fitting is provided, 
the waste pipe from the fitting may connect to the body of the floor drain above its trap seal. 

b. Where required by the sterilizer manufacturer, a floor drain shall be located directly beneath the steril- 
izer within the area of its base. 

14.10.4 Cooling Required 

Waste drainage from condensers or steam traps shall be cooled below 140°F before being discharged indi- 
rectly to the sanitary drainage system. 

14.1 0.5 Traps Required for Bedpan Steamers 

A trap having a minimum seal of 3 inches shall be provided in the indirect waste pipe for a bedpan steamer, 
located between the fixture and the air gap at the indirect waste receptor. 

14.11 VAPOR VENTS AND STACKS FOR STERILIZERS 

14.11.1 General 

Where sterilizers have provisions for a vapor vent and such a vent is required by their manufacturer, a vapor 
vent shall be extended to the outdoors above the roof. Sterilizer vapor vents shall terminate in accordance 
with Section 12.4 and shall not be connected to local vents for clinical sinks or bedpan washers or to any 
drainage system vent. 

14.11.2 Material 

Sterilizer vapor vent piping shall be of a material acceptable for sanitary vents in accordance with Section 3.6. 

14.1 1.3 Required Size and Arrangement 

a. Sterilizer vapor vents and stacks for individual sterilizers shall be not less than the size of the sterilizer 
vent connection, except that stacks shall be not less than 1-1/2" pipe size. Where vapor vent stacks serve 
more than one sterilizer, the cross-sectional area of the stack shall be not less than the aggregate cross- 
sectional areas of the vapor vents for all of the sterilizers served. 

b. In single and multiple installations, the connections to the vapor vent stack shall be made using sanitary 
tee or tee-wye fittings oriented for upward flow from the branch. A branch connection to a sterilizer vapor 
vent stack shall extend not more than 5 feet horizontally and shall be sloped not less than 1/4 inch per foot 
away from the sterilizer and toward the vent stack. 

14.11.4 Provisions for Drainage 

Provisions shall be made for the drainage of vapor condensation within sterilizer vapor vent piping. The base 
of stacks shall drain indirectly through an air gap to a trapped and vented waste receptor connected to the 
sanitary drainage system. 



2006 National Standard Plumbing Code-Illustrated 329 



14.12 DRAINAGE FROM CENTRAL VACUUM SYSTEMS 

14.12.1 General 

Provisions for drainage from medical, surgical, dental, and similar central vacuum systems shall be as required 
by either NFPA 99 - Health Care Facilities or NFPA 99C - Gas and Vacuum Systems. In addition, drainage 
from dental and other vacuum systems that collect fluid waste centrally shall comply with Sections 14.12.2 
through 14.12.4. 

14.12.2 Positive Pressure Drainage from Air/Waste Separators in Dental Vacuum Systems 

a. The waste outlet from an air/waste separator on the discharge side of a vacuum pump or blower shall be 
direct-connected to the sanitary drainage system through a deep-seal trap that is conventionally vented within the 
plumbing system. The trap vent shall extend vertically to not less than 6 inches above the top of the separator 
before making any horizontal turns. The vacuum exhaust air flow from the separator shall be separately vented 
to outodoors as required under NFPA 99 and NFPA 99C. 

b. The trap and drain branch size shall be at least two pipe sizes larger than the waste pipe from the separator, 
butnot less than 1-1/2" pipe size. The vent shall be the full size of the trap and drain. The trap seal shall be at least 
two times the exhaust backpressure in the separator, but not less than 4 inches deep. 

14.12.3 Gravity Drainage from Waste Holding Tanks in Dental Vacuum Systems 

a. The drainage from waste holding tanks shall extend from the vacuum check valve on the waste outlet 
of the tank and be direct-connected to the sanitary drainage system through a deep-seal trap that is conven- 
tionally vented within the plumbing system. In addition, a vent shall be installed between the vacuum check 
valve and the drain trap, on the inlet side of the trap, to seal the check valve when the holding tank is operat- 
ing under vacuum and collecting waste. This vent shall be connected to the plumbing system vents. Both 
vents shall extend vertically to not less than 6 inches above the top of the holding tank before making any 
horizontal turns. 

b. The trap and drain size shall be at least two pipe sizes larger than the waste outlet and vacuum check valve, 
but not less than 2" pipe size. The trap shall be not less than 4 inches deep. The vent for the vacuum check valve 
shall be not less than the size of the check valve. The trap vent shall be not less than one-half the size of the trap 
and drain branch. 

14.12.4 Protection from Sewage Backup in Dental Vacuum Systems 

A floor drain or other trapped and vented receptor shall be provided near the connection of the drain from a dental 
vacuum air/waste separator or waste holding tank to the sanitary drainage system that will overflow in the event 
of a backup in the sanitary drainage system and prevent the backup from reaching the level of the trap for the 
air /waste separator or the drain check valve for the waste holding tank. The trap of the floor drain or receptor 
shall be primed if it does not receive an indirect waste discharge. 



14.13 ASPIRATORS 

Provisions for aspirators or other water-supplied suction devices shall be installed only with the specific approval of 
the Authority Having Jurisdiction. Where aspirators are used for removing body fluids, they shall include a collec- 
tion bottle or similar fluid trap. Aspirators shall indirectly discharge to the sanitary drainage system through an air 
gap, in accordance with Chapter 9. The potable water supply to an aspirator shall be protected by a vacuum 
breaker or equivalent, in accordance with Sections 14.7 and 10.5.3. 



*■'" 2006 National Standard Plumbing Code-Illustrated 









Tests and Maintenance 



15.1 EXPOSURE OF WORK 

New, altered, extended or replaced plumbing shall be left uncovered and unconcealed until it has been tested and 
approved. Where such work has been covered or concealed before it is tested and approved, it shall be exposed 
for testing. K 

15.2 EQUIPMENT, MATERIAL AND LABOR FOR TESTS 

Equipment, material and labor required for testing a plumbing system or part thereof shall be furnished by the 
installing contractor. 

15.3 TESTING OF PLUMBING SYSTEMS 

15.3.1 General 

New plumbing systems and parts of existing systems that have been altered, extended or repaired shall be 
tested as prescribed hereinafter to disclose leaks and defects only when required by the Authority Having 
Jurisdiction. " 

15.3.2 Exceptions 

a. When required by the Authority Having Jurisdiction, where an existing concealed sewer or drain is reused 
as part of a new or renovated drainage system, the line shall be traced to its point of termination and shall be 
tested to determine that: 

1. It is connected to the proper drainage system, such as sanitary or storm, 

2. It will withstand a leak test, and, 

3. It is free-flowing and not restricted. 

15.4 METHODS OF TESTING THE DRAINAGE AND VENT SYSTEMS 

15.4.1 Rough Plumbing 

a. Except for outside leaders and perforated or open jointed drain tile, the piping of plumbing drainage and 
venting systems shall be tested upon completion of the rough piping installation by water or air and proved 
watertight. The Authority Having Jurisdiction may require the removal of any cleanout plugs to ascertain if 
the pressure has reached all parts of the system. Either of the following test methods shall be used. 

1. The water test shall be applied to the drainage system either in its entirety or in sections after rough 
piping has been installed. If applied to the entire system, all openings in the piping shall be tightly closed 
except the highest opening, and the system filled with water to point of overflow. If the system is tested in 



2006 National Standard Plumbing Code-Illustrated 



331 



sections, each opening shall be tightly plugged except the highest opening of the section under test, and each 
section shall be filled with water, but no section shall be tested with less than a 10-foot head of water. In 
testing successive sections at least the upper 10 feet of the next preceding section shall be tested, so that no 
joint or pipe in the building (except the uppermost 10 feet of the system) shall have been submitted to a test of 
less than 10-foot head of water. The water shall be kept in the system or in the portion under test for at least 
15 minutes before inspection starts; the system shall then be tight at all points. 

2. The air test shall be made by attaching an air compressor testing apparatus to any suitable opening and 
after closing all other inlets and outlets to the system, forcing air into the system until there is a uniform gauge 
pressure of 5 pounds per square inch or sufficient to balance a column of mercury 10 inches in height. This 
pressure shall be held without introduction of additional air for a period of at least 1 5 minutes. 

15.4.2 Finished Plumbing 

a. When the rough plumbing has been tested in accordance with section 1 5 .4. 1 , a final test of the finished 
plumbing system may be required to insure that the final fixture connections to the drainage system are gas- 
tight. 

b. After the plumbing fixtures have been set and their traps filled with water, their connections shall be 
tested and proved gas and watertight. A final smoke or peppermint test shall be required, except in the case 
of a previous on site-inspected water or air tested system. If a smoke or peppermint test is required, the 
following test methods shall be employed: 

1 . A smoke test shall be made by filling all traps with water and then reintroducing into the entire system a 
pungent, thick smoke produced by one or more smoke machines. When the smoke appears at stack openings 
on the roof, they shall be closed and a pressure equivalent to a one-inch water column shall be developed and 
maintained for the period of the inspection. 

2. Where the Authority Having Jurisdiction, due to practical difficulties or hardships, finds that a smoke 
test cannot be performed, a peppermint test shall be substituted in lieu thereof. Such peppermint test shall be 
conducted by the introduction of two ounces of oil of peppermint into the roof terminal of every line or stack 
to be tested. The oil of peppermint shall be followed at once by ten quarts of hot (MOT) water whereupon all 
roof vent terminals shall be sealed. A positive test, which reveals leakage, shall be the detection of the odor of 
peppermint at any trap or other point on the system. Oil of peppermint or persons whose person or clothes 
have come in contact with oil of peppermint shall be excluded from the test area. 



Comment: The smoke or peppermint tests on the finished plumbing can be waived by the Authority 
Having Jurisdiction when they are considered to be unnecessary. However, the finished plumbing tests 
should be performed if the installation appears to be improper or there is the odor of sewer gas. 



15.5 METHOD OF TESTING BUILDING SEWERS 

The building sewer shall be tested by insertion of a test plug at the point of connection with the public sewer, 
private sewer, individual sewer disposal, or other point of disposal. It shall then be filled with water under a head of 
not less than 10 feet. The water level at the top of the test head of water shall not drop for at least 15 minutes. 
Where the final connection of the building sewer cannot reasonably be subjected to a hydrostatic test, it shall be 
visually inspected. 



332 2006 National Standard Plumbing Code-Illustrated 



15.6 METHODS OF TESTING WATER SUPPLY SYSTEMS 

a. Upon completion of a section or the entire water supply system, it shall be tested and proved tight under a 
water pressure not less than the working pressure under which it is to be used or 80 pounds per square inch, 
whichever is greater. 

b. For metallic pipe and where the Authority Having Jurisdiction determines that providing potable water for the 
test represents a hardship or practical difficulty, the system may be tested with air to the pressures noted above, as 
allowed by the pipe manufacturer. 

c. For plastic pipe, testing by compressed gas or air pressure shall be prohibited. 

d. Piping shall be disinfected after testing per Section 10.9. 

15.7 DEFECTIVE PLUMBING 

Where there is reason to believe that the plumbing system of any building has become defective, it shall be sub- 
jected to test or inspection and any defects found shall be corrected. 

1.5.8 MAINTENANCE 

15.8.1 General 

The plumbing and drainage systems shall be maintained at all times in compliance with the provisions of this 
Code. 

15.8.2 Exception 

Existing plumbing installed under prior regulations or lack thereof, may remain unchanged unless immediate 
hazards to health, life, or property are evident. 



2006 National Standard Plumbing Code-Illustrated 333 



Blank Page 



2006 National Standard Plumbing Code-Illustrated 



^OT'^'ll^'^V.l^ 1 ^''-'^^^^^[>--! MIM S S liliS^IU lB IIB M ii 




Regulations Governing Individual Sewage Disposal 

Systems for Homes and Other Establishments Where 

Public Sewage Systems Are Not Available 



16.1 GENERAL PROVISIONS 



16.1.1 General 



In the absence of State or other local laws governing the installation, use and maintenance of private sewer 
disposal systems, the provisions of this Chapter shall apply. 

16.1.2 Sewage Disposal 

"Sewage disposal" under this section shall mean all private methods of collecting and disposing of domestic 
sewage, including septic tanks. 

1.6.1.3 Domestic Sewage 

Domestic sewage shall be disposed of by an approved method of collection, treatment and effluent discharge. 
Domestic sewage or sewage effluent shall not be disposed of in any manner that will cause pollution of the 
ground surface, ground water, bathing areas, lakes, ponds, watercourses, tidewater, or create a nuisance. It 
shall not be discharged into any abandoned or unused well, or into any crevice, sink hole, or other opening 
either natural or artificial in a rock formation. 



Comment: Federal and local environmental agencies have criteria for the allowable contaminant levels 
that can be discharged into a water course or other point of discharge. Improper disposal of sewage can 
result in; (1) contamination of public or private water supplies, (2) spread of disease by insects or vermin, 
(3) creation of objectionable odors, (4) pollution of public water resources, or (5) other conditions that 
are detrimental to public health and safety. 



16.1.4 Non-Water-Carried Sewage 

When water under pressure is not available, all human body wastes shall be disposed of by depositing them in 
approved privies, chemical toilets, or such other installations acceptable to the Authority Having Jurisdiction. 

16.1.5 Water-Carried Sewage 

Water-carried sewage from bathrooms, kitchens, laundry fixtures and other household plumbing shall pass 
through a septic or other approved sedimentation tank prior to its discharge into the soil or into a sand filter. 
Where underground disposal or sand filtration is not feasible, consideration shall be given to special methods 
of collection and disposal. 



2006 National Standard Plumbing Code-Illustrated 33c 



16.1.6 Responsibility 

The installing contractor is responsible for compliance with these regulations. 

16.1.7 Abandoned Disposal Systems 

Abandoned disposal systems shall be disconnected from the buildings, pumped out and filled with earth. 



Comment: This requirement applies to all abandoned dry wells, septic tanks, cesspools, distribution 
boxes, seepage pits, and other structures that have handled sewage or sewage by-products. 



16.1.8 Absorption Capacity 

No property shall be improved in excess of its capacity to properly absorb sewage effluent in the quantities 
and by means provided for in this Code. (See Section 2.19.2.) See Sections 16.5 and 16.6 



Comment: The development of properties must be limited by the ability of the soil to absorb the effluent 
of the required sewage disposal system. Bacterial action within the soil provides secondary treatment of 
the effluent from septic tanks. 



16.1.9 Reserved 

16.1.10 Higher Compliance 

Nothing contained in this Chapter shall be construed to prevent the Authority Having Jurisdiction from requir- 
ing compliance with higher requirements than those contained herein where such higher requirements are 
essential to maintain a safe and sanitary condition. 

16.2 RESERVED 

16.3 DESIGN OF INDIVIDUAL SEWAGE SYSTEM 

16.3.1 Design 

The design of the individual sewage disposal system must take into consideration location with respect to 
wells or other sources of water supply, topography, water table, soil characteristics, area available, and 
maximum occupancy of the building. See Sections 16.4 through 16.12 



Comment #1: The primary factors in the design of private sewage disposal systems are; (1) the location 
of the disposal system, (2) the absorption capacity of the soil, (3) the size of the drainage field, (4) the 
size of the septic tank, (5) the elevation of the ground water table, (6) the location of water supplies for 
the property and neighboring properties, (7) the use and population of the building(s) served, (8) the 
topography of the property. 

Comment #2: Problems with topography (elevation differences) can be overcome by sewage pumps, 
which can pump to elements of the disposal system that are at higher elevations than others. 



336 2006 National Standard Plumbing Code-Illustrated 



16.3.2 Type of System 

The type of system to be installed shall be determined on the basis of location, soil permeability and ground- 
water elevation. See Sections 16.4 and 16.5. 

16.3.3 Sanitary Sewage 

The system shall be designed to receive all sanitary sewage, including laundry waste, from the building. 
Drainage from footings or roofs shall not enter the system. & 



Comment: Storm water and foundation drains must not be connected to a private sewage disposal 
system. 



16.3.4 Discharge 

The system shall consist of a septic tank discharging into either a subsurface disposal field or one or more 
seepage pits or into a combination of both, if found adequate as such and approved by the Authority Having 
Jurisdiction. See Figure 1.2.45 and the definitions of "Septic Tank" and "Leaching Well or Pit". 

16.3.5 Backflow 

Plumbing fixtures connected to a private sewage disposal system that are subject to backflow, shall be 
protected by a backwater valve or a sewage ejector. 



Comment: Where plumbing fixtures connected to a private sewage disposal system are subject to 
backflow from a blockage in the disposal system, they must be protected by a backwater valve. Sewage 
pumps and ejectors having check valves provide this protection for the fixtures that they serve. 



16.3.6 Reserved 

16.3.7 Design Criteria 

Design criteria for sewage flows shall be selected according to type of establishment. (See Table 16.3.7.) 



2006 National Standard Plumbing Code-Illustrated 



337 



Table 16.3.7 
SEWAGE FLOWS ACCORDING TO TYPE OF ESTABLISHMENT 

Type of Establishment 



Schools (toilets and lavatories only) 15 Gal. per day per person 

Schools (with above plus cafeteria) 25 Gal. per day per person 

Schools (with above plus cafeteria and showers) 35 Gal. per day per person 

Day workers at schools and offices 15 Gal. per day per person 

Day camps 25 Gal. per day per person 

Trailer parks or tourist camps (with built-in bath) 50 Gal. per day per person 

Trailer parks or tourist camps (with central bathhouse) 35 Gal. per day per person 

Work or construction camps 50 Gal. per day per person 

Public picnic parks (toilet wastes only) 5 Gal. per day per person 

Public picnic parks (bathhouse, showers and flush toilets) 10 Gal. per day per person 

Swimming pools and beaches 10 Gal. per day per person 

Country clubs 25 Gal. per day per person 

Luxury residences and estates 150 Gal. per day per person 

Rooming houses 40 Gal. per day per person 

Boarding schools 50 gal. per day per person 

Hotels (with connecting baths) 50 Gal. per day per person 

Hotels (with private baths-2 persons per room 100 Gal. per day per person 

Boarding schools 100 Gal. per day per person 

Factories (gallons per person per shift-exclusive of 

industrial waste) 25 Gal. per day per person 

Nursing homes 75 Gal. per day per person 

General hospitals 150 Gal. per day per person 

Public institutions (other than hospitals) 100 Gal. per day per person 

Restaurants (toilet and kitchen wastes per unit of 

serving capacity) 25 Gal. per day per person 

Kitchen wastes from hotels, camps, boarding houses, etc. 

serving three meals per day 10 Gal. per day per person 

Motels 50 Gal. per bed space 

Motels with bath, toilet, and kitchen wastes 60 Gal. per bed space 

Drive-in theatres 5 Gal. per car space 

Stores 400 Gal. per toilet room 

Service .'stations' Z 10 Gal. per vehicle served 

Airports 3-5 Gal. per passenger 

Assembly hails 2 Gal. per seat 

Bowlingalleys 75 Gal. per lane 

Churches (small) 3-5 Gal. per sanctuary seat 

Churches (large with kitchen) 5-7 Gal. per sanctuary seat 

Dance halls 2 Gal. per day per person 

Laundries (coin operated) 400 Gal. per machine 

Service stations 1000 Gal. (First Bay) 

500 Gal. (Each add. Bay) 

Sub-divisions or individual homes 75 Gal. per day per person 

Marinas-Flush toilets 36 Gal. per fixture per hr 

Urinals 10 Gal. per fixture per hr 

Wash basins 15 Gal. per fixture per hr 

Showers 150 Gal. per fixture per hr 



33g 2006 National Standard Plumbing Code-Illustrated 



16.4 LOCATION OF INDIVIDUAL SEWAGE SYSTEM 

16.4.1 Reserved 

16.4.2 Reserved 

16.4.3 Minimum Distances 

The minimum distances that shall be observed in locating the various components of the disposal system shall 
be as given in Table 16.4.3. 



Table 16.4.3 

MINIMUM DISTANCE BETWEEN COMPONENTS 

OF AN INDIVIDUAL SEWAGE DISPOSAL SYSTEM (in feet) 1 




Shallow 
Well 


Deep 

Well 


Single 

Suction 

Line 


Septic 
Tank 


Distribution 
Box 


Disposal 
Field 


Seepage 
Pit 


Dry 
Well 


Property 
Line 


Building' 


Bldg. Sewer 
other than 
cast-iron 


50 


50 


50 
















Bldg. Sewer 
cast-iron 


10 


10 


10 
















Septic Tank 


100 


50 


50 


- 


5 


10 


10 


10 


10' 


10 


Distribution 
Box 


100 


50 


50 


5 






5 


5 


10 


20 


Disposal 
Field 


100 


50 


50 


10 


5 


_ 






10 


20 


Seepage 
Pit 


100 


50 


50 


10 


5 


_ 






10 


20 


Dry Well 


100 


50 


50 


10 


5 








10 


20 


Shallow 
Well 


— 


_ 


.„ 


100 


100 


100 


100 


100 






Deep 
Well 


— 


„. 


_ 


50 


50 


50 


50 


50 






Suction 
Line 


„ 




_ 


50 


50 


50 


50 


50 






'May be closer to building when permission is given by the Authority Having Jurisdiction 



16.4.4 General 

All sewage disposal systems shall conform with the following general principles regarding site: 

16.4.4.1 Location 

Sewage disposal system shall be located at the lowest point on the premises consistent with the general 
layout topography and surroundings, including abutting lots. Locations at a higher elevation through 
employment of a forced system may be used with the specific approval of the Authority Having 
Jurisdiction. 

16.4.4.2 Watersheds 

Sewage disposal facilities shall not be located on any watershed for a public water supply system. 

16.4.4.3 Septic Tanks and Underground Disposal 

Septic tanks and underground disposal means shall not be within 200 feet measured horizontally from 



2006 National Standard Plumbing Code-Illustrated 



339 



the high water level in a reservoir or the banks of tributary streams when situated less than 3,000 feet 
upstream from an intake structure. 

16.4.4.4 Beyond 3,000 feet 

Sewage disposal facilities situated beyond 3,000 feet upstream from intake structures shall be located 
no less than 100 feet measured horizontally from the high water level in the reservoir or the banks of 
tributary streams. 

16.4.4.5 Percolation Test 

Prior to approval, the soil must prove satisfactory by the standard percolation test when underground 
disposal is used. See Section 16.5 

16.5 PERCOLATION TEST 

Percolation tests to determine the absorption capacity of soil for septic tank effluent shall be conducted in the 
following manner: 

16.5.1 Subsurface Irrigation 

When subsurface irrigation is contemplated, a test pit shall be prepared 2 feet square and not less than 1 foot 
deep. At the time of conducting the percolation test, a hole 1 foot square and 1 foot deep shall be prepared in 
the test pit. 

16.5.2 Water Depth 

The hole shall be filled with water to a depth of 7 inches. For pre-wetting purposes, the water level shall be 
allowed to drop 6 inches before time of recording is started. 

16.5.3 Time Expired 

The time required for the water level to drop 1 inch from 6 inches to 5 inches in depth shall be noted and the 
length of tile in the subsurface irrigation system shall be obtained from Section 16.5.4. In no case, however, 
shall less than 1 00 feet of tile be installed when 1 foot trenches are used. 

16.5.4 Tile Length 

The tile lengths, in feet, for each 100 gallons of sewage per day are as follows: 



Time in Minutes Trench Width 

for 1-inch Drop 1-foot 2-feet 3-feet 



1 25 13 9 

2 30 15 10 

3 35 18 12 
5 42 21 14 

10 59 30 20 

15 74 37 25 

20 91 46 31 

25 105 53 35 

30 125 63 42 



Comment: Determine the total daily sewage flow for the system from Table 16.3. 7. Divide this number 
by 100 and determine the required length and number of tiles in the underground disposal system. 



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2006 National Standard Plumbing Code-Illustrated 



16.5.5 Seepage Pits 

When seepage pits are contemplated, test pits approximately 5 feet in diameter to permit a man entering the 
pit by means of a ladder and to such depth as to reach a porous soil shall be prepared. In the bottom of this 
pit, a 1 foot square by 1 foot deep hole shall be made at the time of testing and the percolation test conducted 
as indicated under Sections 16.5.1, 16.5.2, and 16.5.3. See the definition of "Leaching Well or Pit" and 
Figure 1.2.41. 



Comment: Observe safety requirements regarding sheeting, shoring, and bracing for deep excavations. 



16.5.6 Seepage Pit Absorption Area 

The absorption area of a seepage pit required shall be obtained from Table 1 6.5.6. In no case, however, shall 
the absorption area in the porous soil be less than 125 square feet. The bottom of the pit shall not be consid- 
ered part of the absorption area. 



Comment: The absorption area of a seepage or leaching pit is the square foot area of the sidewalls. The 
sidewall area = 3.1416 x diameter x depth (both in feet). 



Table 16.5.6 
REQUIRED ABSORPTION AREA IN SEEPAGE PITS FOR EACH 100 GALLONS OF 

SEWAGE PER DAY 



Time in Minutes Effective Absorption Area 

1 for 1-inch Drop Square Feet 



1 32 

2 40 

3 45 
5 56 

10 75 

15 96 

20 108 

25 139 

30 167 



16.5.7 Thickness of Porous Soil 

The thickness of the porous soil below the point of percolation test must be determined by means of digging a 
pit or using a soil auger. The effective absorption area shall be calculated only within this porous soil. 

16.6 CAPACITY OF SEPTIC TANKS 

16.6.1 Liquid Capacity 

The liquid capacity of all septic tanks shall conform to Tables 16.3.7 and 16.6.1 as determined by the number 
of bedrooms or apartment units in dwelling occupancies and the occupant load or the number of plumbing 
fixture units as determined from Table 11.4.1, (whichever is greater) in other building occupancies. 



Comment: The septic tank sizes in Table 16.6.1 have allowances for sludge storage space and the use of 
domestic food waste disposal units. 



2006 National Standard Plumbing Code-Illustrated 34 \ 





Table 16.6.1 






CAPACITY OF SEPTIC TANKS 






Multiple 


Other uses; 


Minimum 


Single family 


dwellings units or 


maximum 


septic tank 


dwelling-number 


apartments-one 


fixture 


capacity in 


ofbedrooms 


bedroom each 


units served 


gallons 


1-3 




20 


1000 


4 


2 units 


25 


1200 


5 or 6 


3 


33 


1500 


7 or 8 


4 


45 


2000 




5 


55 


2250 




6 


60 


2500 




7 


70 


2750 




8 


80 


3000 




9 


90 


3250 




10 


100 


3500 


Extra bedroom: 150 gallons each. 






Extra dwelling units over 10:250 gallons each. 






Extra fixture units over 100: 25 gallons per fixture unit. 





16.6.2 Reserved 

16.6.3 Multiple Compartment 

In a tank of more than one compartment, the inlet compartment shall have a capacity of not less than two- 
thirds of the total tank capacity. 



Comment: Septic tanks with two compartments operate more efficiently than single-compartment tanks 
at removing solids in the effluent. The liquid that enters the second compartment is already substantially 
clarified. There is less turbulence in the second chamber, which permits finer suspended solids to settle 
out 



16.6.4 Septic Tank Materials 

See Sections 3.3.11, 16.6.5 and 16.6.6. 



Comment: Modern septic tanks are typically constructed of concrete (pre-cast), polyethylene, or fiber- 
glass. Steel septic tanks are prohibited by many jurisdictions because of leakage due to corrosion. 



16.6.5 Steel Tanks 



Comment: Steel septic tanks are no longer approved by most jurisdictions because of leakage due to 
corrosion. The average life expectancy of a steel septic tank is only 7 years. 



16.6.5.1 Welding 

All steel tanks shall be continuous welded. (No spot welding is permitted.) 



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2006 National Standard Plumbing Code-Illustrated 



16.6.5.2 Wall Thickness 

The minimum wall thickness of any steel septic tank shall be No. 12 U.S. gauge (0.109"). 

16.6.5.3 Coatings 

Metal tanks shall be coated inside and out with an approved coating. 

16.6.5.4 Baffles 

The inlet and outlet baffles shall be at least 12 inches in diameter at the point opposite the opening in 
the tank. 

16.6.5.5 Pumpout Opening 

The pumpout opening in the top shall be large enough to permit a 6-inch cast-iron pumpout pipe to be 
inserted with a shoulder to support this pipe. 

16.6.5.6 Tank Opening 

The tank opening shall not be smaller than 6 inches with a 3 -inch collar. 

16.6.5.7 Outside Diameter of Collar 

The outside diameter of this collar shall be 8 inches. 

16.6.5.8 Pumpout Pipe 

The pumpout pipe shall terminate at the surface and a 6-inch iron body brass cleanout shall be caulked 
into the hub of this pipe with oakum and molten lead; the cleanout nut shall be solid brass no smaller 
than one inch. 

16.6.5.9 Manhole 

There shall be a 24 x 24-inch manhole held in position by four 3/8" bolts securely welded in place. 

16.6.5.10 Partition 

There shall be a supporting partition welded in the center of these tanks as per drawings. 

16.6.5.11 Partition Openings 

This partition shall have 2-inch openings at intervals at the top for air circulation. 

16.6.5.12 Capacity, Gauge Metal and Weight 

The capacity, gauge metal, and weight must be stamped on a brass plate and welded to the top of 
metal septic tanks. 

16.6.6 Concrete Tanks 

16.6.6.1 Baffles 

Concrete tanks shall have the same size baffles and pumpout openings as for steel tanks. 



2006 National Standard Plumbing Code-Illustrated 343 



16.6.6.2 Tops 

The tops shall have a 24-inch manhole with handle to remove same, or be cast in three or four sections 
cemented in place. 

16.6.6.3 Wall Thickness 

The minimum thickness of the walls shall be 2-3/4 inches. 

16.6.6.4 Tops and Bottoms 

The tops and bottoms shall be 4 inches thick unless placed under a driveway, then they shall be a 
minimum of 6 inches. 

16.6.6.5 Walls and Bottoms 

All tank walls and bottoms shall be reinforced with approved reinforcing. 

16.6.6.6 Top Reinforcing 

The tops shall have 3/8 inch steel reinforcing on 6-inch centers. 

16.6.6.7 Watertight 

The tank shall be watertight. 

16.6.7 Depth of Septic Tank 

The top of the septic tank shall be brought to within 36 inches of the finished grade. Where a greater depth is 
permitted by the Authority Having Jurisdiction, the access manhole must be extended to the finished grade 
and the manhole shall have a concrete marker at grade. 



Comment: The typical depth of cover on the top of a septic tank is 12" - 18". Where the depth of cover 
exceeds 36 ", the structural design of the tank must be adequate for the imposed earth loads. 



16.6.8 Limitation 

No septic tank shall serve more than one property unless authorized by the Authority Having Jurisdiction. 

16.6.9 Effluent 

The effluent from all septic tanks shall be disposed of underground by subsurface irrigation or seepage pits or 
both. 

16.7 DISTRIBUTION BOX 

16.7.1 When Required 

A distribution box shall be required when more than one line of subsurface irrigation or more than one seep- 
age pit is used. 



Comment: The minimum distances from distribution boxes to the septic tank, disposal field, seepage pit, 
dry well, potable water wells, or suction lines from potable water wells must be in accordance with Table 
16.4.3. 



344 2006 National Standard Plumbing Code-Illustrated 



16.7.2 Connection 

Each lateral line shall be connected separately to the distribution box and shall not be subdivided. 

16.7.3 Invert level 

The invert of all distribution box outlets shall be at the same level and approximately 2 inches above the 
bottom of the box. The inlet invert shall be at least 1 inch above the invert of the outlets. The size of the 
distribution box shall be sufficient to accommodate the number of lateral lines. 

16.7.4 Watertight 

The distribution box shall be of watertight construction arranged to receive the septic tank effluent and with 
an outlet or connecting line serving each trench or seepage pit. 

16.7.5 Baffle 

A baffle at least 6 inches high and 12 inches long shall rest on the bottom of the box and be placed at right 
angles to the direction of the incoming tank effluent and 12 inches in front of it. 

16.7.6 Reserved 

16.7.7 Inspection 

The sides of the box shall extend to within a short distance of the ground surface to permit inspection, and 
shall have a concrete marker at grade. 

16.8 SEEPAGE PITS 

16.8.1 Use 

Seepage pits may be used either to supplement the subsurface disposal field or in lieu of such field where 
conditions favor the operation of seepage pits, as may be found necessary and approved by the Authority 
Having Jurisdiction. See Figure 1.2.41 and the definition of "Leaching Well or Pit" 

16.8.2 Water Table 

Seepage pits shall not penetrate the water table. 

16.8.3 Septic Tank Effluent Disposal 

Where seepage pits are used for septic tank effluent disposal, the number, diameter and depth of the pits shall 
be determined after percolation tests have been made to ascertain the porosity of the soil. See Section 
16.5.5 

16.8.4 Excavation 

The excavation for a seepage pit shall be greater in diameter than the outside diameter of the vertical 
sidewalls to allow for the footing. 

16.8.5 Annular Space 

The annular space between the outside of the vertical walls and the excavation shall be backfilled with broken 
stone, coarse gravel, or other suitable material. 



2006 National Standard Plumbing Code-Illustrated 345 



16.8.6 Construction 

Seepage pits shall be constructed with the bottom being open with an outer ring, or footing, to support the 
sidewalls. 

16.8.7 Sidewalls 

The sidewalls shall be made of pre-cast concrete, stone, concrete or cinder blocks, or brick laid in cement 
mortar for strength, with openings at sufficient intervals to permit the septic tank effluent to pass out through 
the wall to the surrounding porous soil. 

16.8.8 Cover Strength 

All septic tank tops and seepage pit covers shall be of sufficient strength to carry the load imposed. Seepage 
pit covers shall be at least as required in Sections 16.8.9, 16.8.10, and 16.8.1 1. 

16.8.9 Pre-CastTop 

Seepage pit tops shall be pre-cast, reinforced concrete (2,500 pounds per square inch minimum compressive 
strength) not less than 5 inches thick and designed to support an earth load of not less than 400 pounds per 
square foot. Each such cover shall extend not less than 3 inches beyond the sidewalls of the pit, shall be 
provided with a 6-inch minimum inspection hole with pipe extended to the surface, and a 6-inch cast-iron 
standpipe with cleanout at grade. 

16.8.10 Depth Below Grade 

The top shall be at least 36 inches below finished grade, except where less is permitted by the Authority 
Having Juri sdiction . 

16.8.11 Field Fabricated Slabs 

Where field fabricated slabs are used, Table 16.8.1 1 indicates the requirements. 



Table 16.8.11 
DESIGN OF SEEPAGE PIT COVERS 


Pit 
Diameter 


Pit Wall Cover Cover 
Thickness Thickness Weight 


Reinforcing Steel Req'd in 

Two Perpendicular 

Directions 




5ft. 

6ft. 

8ft. 

10ft. 


4" 5" 
8" 5" 
8" 6" 
8" 8" 


12301b 
17701b 
37801b 
7850 lb 


#5@10'/ 2 "c/c 
#5 @ 9" c/c 
#5 @ Tii" c/c 
#5 @ 6'h" c/c 





16.9 ABSORPTION TRENCHES 

16.9.1 General 

Absorption trenches shall be designed and constructed on the basis of the required effective percolation area. 



346 



2006 National Standard Plumbing Code-Illustrated 



16.9.2 Filter Material 

The filter material shall cover the tile and extend the full width of the trench and shall be not less than 6 
inches deep beneath the bottom of the tile, and 2 inches above the top of the tile. The filter material may be 
washed gravel, crushed stone, slag, or clean bank-run gravel ranging in size from 1/2 to 2-1/2 inches The 
filter material shall be covered with burlap, filter cloth, 2 inches of straw, or equivalent permeable material 
prior to backfilling the excavation. 

16.9.3 Absorption Field 

The size and minimum spacing requirements for absorption fields shall conform to those given in Table 16.9.3. 



Table 16.9.3 
SIZE AND SPACING FOR DISPOSAL FIELDS 


Width of 
trench at 
bottom 
(in.) 


Recommended 
depth of 
trench 
(in.) 


Spacing tile 
lines 1 
(ft.) 


Effective 
absorption area 
per lineal ft. of 
trench (sq. ft.) 


18 

24 
30 
36 


18 to 30 
18 to 30 
18 to 36 
24 to 36 


6.0 

6.0 
7.6 
9.0 


1.5 
2.0 
2.5 
3.0 


I. A greater spacing is desirable where available area permits. ' " "~'~ 



16.9.4 Lateral Length 

Length of laterals shall not exceed 100 feet. 



Comment: Where the length of lateral tiles in Section 16.5.4 exceeds 100 feet, two or more laterals must 
be provided. 



16.9.5 Absorption Lines 

Absorption lines shall be constructed of 4" pipe of open jointed or perforated vitrified clay pipe, open jointed or 
horizontally split or perforated clay tile, perforated plastic pipe or open jointed cast iron soil pipe, all conform- 
ing to approved standards. In the case of clay tile, open jointed clay pipe, or open jointed cast-iron soil pipe, 
the sections shall be spaced not more than 1/2 inch apart, and the upper half of the joint shall be protected 'by 
asphalt-treated paper while the piping is being covered. 

16.9.6 Grade 

The trench bottom shall be uniformly graded to slope from a minimum of 2 inches to a maximum of 4 inches 
per 100 feet. 

16.10 RESERVED 



2006 National Standard Plumbing Code-Illustrated 



347 



16.11 PIPING MATERIAL 

See Chapter 3. 



Comment: Refer to Section 3.5 and Table 3.5 for approved materials for drainage piping. Refer to 
Section 16.9.5 and Table 3.8 for approved materials for sub-soil drainage and absorption lines. 



16.12 SAND FILTERS 

16.12.1 General Specifications for Design and Construction of a Sand Filter with Chlorination 

16.12.1.1 General 

A sand filter shall consist of a bed of clean, graded sand on which septic tank effluent is distributed by 
means of a siphon and pipe, with the effluent percolating through the bed to a series of underdrains 
through which it passes to the point of disposal. See the definition of "Sand Filter" and Figure 
1.2.51. 

16.12.1.2 Filter Size 

The filter size shall be determined on the basis of 1 . 1 5 gallons per square foot per day if covered, and 
2.3 gallons per square foot per day if an open filter is to be used. 

16.12.1.3 Dosing Tank Size 

The septic tank effluent shall enter a dosing siphon tank of a size to provide a 2-inch coverage of the 
sand filter. 

16.12.1.4 Siphon 

The siphon shall be of a commercial type and shall discharge the effluent to the sand filter intermit- 
tently. The siphon shall be omitted if a pump is used to lift the septic tank effluent to the sand filter. 

16.12.1.5 Surge Tank 

A surge tank shall be used to receive the pump discharge prior to dosing on the sand filter. 

16.12.1.6 Underdrains 

Four-inch diameter vitrified clay pipe in 2-foot lengths laid with 1/2 inch open joints or unglazed farm 
tile in 1 -foot lengths laid with open joints, with the top half of each joint covered with 4-inch wide strips 
of tar paper, burlap, or copper screen, or perforated bituminized-fiber pipe or other approved material 
shall be used for the underdrains. 

16.12.1.7 UnderdrainBed 

The underdrains shall be laid at the bottom of the sand filter, surrounded by washed gravel, crushed 
stone, slag, or clean bank-run gravel ranging in size from 1/2 inch to 2-1/2 inches and free of fines, 
dust, ashes or clay. The gravel shall extend from at least 2 inches below the bottom of the tile to a 
minimum of 2 inches above the top of the tile. 



348 2006 National Standard Plumbing Code-Illustrated 



16.12.1.8 Underdrain Slope and Spacing 

The underdrains shall have a slope from 2 inches to 4 inches per 100 feet and shall be placed at 6-foot 
to 8-foot intervals. 

16.12.1.9 Underdrain Fill 

Above the gravel or other material surrounding the underdrain shall be placed 2 feet of washed and 
graded sand having an effective size of from 0.35-0.5 mm and a uniformity coefficient of not over 3.5. 
(The effective size of a sand filter is that size of which 10% by weight is smaller and the uniformity 
coefficient is the ratio of that size of which 60% by weight is smaller to the effective size.) 

16.12.1.10 Distribution Pipes 

The distribution pipes shall be laid at the surface of the sand filter, surrounded by gravel as specified 
for the underdrains. 

16.12.1.11 Gravel Cover 

The gravel should be covered with untreated building paper and the entire area covered with a mini- 
mum of 12 inches of earth if the filter is to be covered. 

16.12.1.12 Open Filter 

If the filter is an open one, the four sides shall be constructed of wood or concrete to prevent earth 
erosion from entering the sand filter bed. 

16.12.1.13 Chlorine Contact Tank 

The chlorine contact tank for disinfection of sand filter effluent shall provide 20 minutes detention at 
average flow, but in no case shall it be smaller than 50 gallons capacity. Chlorine control should be 
provided by the use of hypochlorite or chlorine machines commercially available. 



2006 National Standard Plumbing Code-Illustrated t^q 



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350 2006 National Standard Plumbing Code-Illustrated 



Potable Water Supply Systems 



17.1 GENERAL REGULATION 



17.1.1 Jurisdiction 

The regulations in this chapter apply to any water system where plumbing fixtures are installed for human 
occupancy. 



Comment: This chapter applies to private water supply systems serving one or more 
buildings independent of any public water supply. 



17.1.2 Pumps 

Pumps shall be installed only in wells, springs and cisterns that comply with the rules and regulations as 
determined by the Authority Having Jurisdiction. 

17.2 QUANTITY OF WATER REQUIRED 



17.2.1 Single Dwelling Unit 

The minimum capacity of the system in gallons per minute shall equal the number of fixtures installed. 



Comment: A capacity of 1 GPM per fixture in a single dwelling unit is a rough rule of 
thumb. The peak demand should be verified using Tables 10.14.2A and 10.14.2B. See 
Section 17.2.4 where well yields do not satisfy the peak demand. 



17.2.2 Other Than a Single Dwelling Unit 

In other than a single dwelling unit, the water system shall be designed in accordance with Tables 10.14.2A, 
and I0.14.2B and shall be capable of supplying the maximum demand to the system according to usage, but, 
in no case, less than for a minimum period of 30 minutes. 



Comment: See Section 10.14.3 for determining the peak demand on the potable water 
supply system. 



2006 National Standard Plumbing Code-lllustraled 



351 



17.2.3 Available Water 

Total water available during any 24-hour period shall not be less than the requirements of Table 16.3.7. 



Comment: Table 16.3.7 indicates the daily design sewage flows from various establish- 
ments. The available water supply must be able to satisfy this daily volume requirement, as 
well as the peak GPM demand. 



17.2.4 Secondary Sources of Water 

a. When the available primary source of water does not meet the minimum requirement of Sections 1 7.2.1 , 
17.2.2, and 17.2.3, one of the following methods shall be used: 

1. Pressure tank of sufficient size. 

2. Gravity tank, see Section 10.8. 

3. Two pump system. 

(a) The capacity of the first well pump shall not exceed the well capacity in flow. This pump supplies 
water to another tank that stores the water at atmospheric pressure and has a control to start and stop the 
pump. 

(b) The second pump delivers the water to a hydropneumatic tank at the required pressure and quantity. 



Comment: Where the primary potable water supply source cannot provide sufficient 
volume to satisfy the 24-hour demand of the water distribution system, water storage facili- 
ties must be provided 



17.3 PRESSURE 

Pressure shall be as required in Section 10.14.3. 



Comment: Private potable water supply systems must provide adequate pressure for 
fixtures to deliver the flow rates for the various fixtures listed in Section 10.14.2. 



11 A PIPING MATERIALS 

Piping from the well to inside of the dwelling shall be as required in Section 3.8. 



Comment: See Sections 3.4.1 and 3.4.2 for general requirements. See Table 3.4 for 
approved materials for water service piping. 



17.5 STORAGE TANKS 

Storage equipment shall be as follows: 

17.5.1 Certified Tanks 

All tanks shall be certified under Water Systems Council Standards for size and pressure. 

17.5.2 TankMaterial 

All tanks shall be coated or made of material to resist corrosion. 



•'5-* 2006 National Standard Plumbing Code-Illustrated 



17.5.3 Pressure Rating 

Hydropneumatic tanks shall have a working pressure rating in excess of the maximum required system 
pressure. 

17.5.4 Non-Toxic Materials 

All tanks shall be constructed of materials and/or coatings that are non-toxic. 

17.5.5 Drain Required 

All tanks shall be provided with a means for draining. 

17.5.6 Covers 

Atmospheric storage tanks shall be provided with a cover as required in Section 10.8. 

17.6 PUMPS 

1 7.6.1 Certified Pumps 

Pumps shall be certified under Water Systems Council Rating and Rating Standards. 



Comment #1: Well pumps for private water supplies include shallow well jet pumps, deep 
well jet pumps, and submersible pumps. 

Comment #2: Jet pumps circulate water through an ejector fitting that develops a vacuum 
and draws water from the well. Shallow well jet pumps are used for wells less than 25 feet 
deep and have the ejector fitting located outside of the well. Deep well jet pumps can be 
used for wells up to 75 feet deep and have the ejector fitting located within the well casing. 
Some jet pumps are convertible and can be used for either one-pipe shallow well or two-pipe 
deep well installations, although their rated capacity is less for deep wells than for shallow 
wells. 

Comment #3: Submersible well pumps are located at the bottom of the drop pipe within the 
well casing. Submersible well pumps can lift water up to 500 feet or more. 



17.6.2 Installation 

Pumps shall be installed in accordance with the manufacturer's recommendations. 

17.6.3 Equipment Installation 

Pumping equipment shall be installed to prevent the entrance of contamination or objectionable material either 
into the well or into the water that is being pumped. 

17.6.4 Pump Location 

The pump shall be located to facilitate necessary maintenance and repair, including overhead clearance for 
removal of drop pipe and other accessories. 



2006 National Standard Plumbing Code-Illustrated 353 



17.6.5 Pump Mounting 

The pump shall be suitably mounted to avoid objectionable vibration and noise, and to prevent damage to 
pumping equipment. 

17.6.6 Pump Accessories 

The pump controls and/or accessories shall be protected from weather. 

17.7 PUMP DOWN CONTROL 

17.7.1 Tailpipe 

30 feet of tailpipe shall be installed below the jet on deep well installation. 

17.7.2 Switches 

Low pressure cut-off switch and/or water level cut-off switch shall be installed. 

17.7.3 Suction Pipe 

Use a vertical suction pipe of 30-foot length on shallow well jet installation. 

17.8 CONTROLS 

a. The following controls are required on all pump installations: 

1. Pressure switch 

2. Thermal overload switch 

3. Pressure relief valve on positive displacement pumps 

4. Low water cut-off switch where the pump capacity exceeds the source of water. 

17.9 WELL TERMINAL 

17.9.1 Upper Well Terminal 

Well casing, curbs and pitless adapters shall terminate not less than eight inches above the finished ground 
surface or pump house floor and at least 24 inches above the maximum high water level where flooding 
occurs. No casing shall be cut off or cut in below ground level except to install a pitless adapter. 

17.9.2 Pitless Adapter 

17.9.2.1 Design 

Pitless adapters designed to replace a section of well casing or for attachment to the exterior of a well 
casing shall be constructed of materials that provide strength and durability equal to the well casing. 

17.9.2.2 Installation 

Installation shall be by threaded, welded or compression-gasketed connection to cutoff casing or 
attachment to the exterior wall of the casing and shall be watertight. 

17.9.2.3 Adapter Units 

Adapter units designed to replace a section of the well casing shall extend above the finished ground 
surface as provided in Section 17.9.1. The top of the adapter unit shall be capped with a cover having a 



354 2006 National Standard Plumbing Code-Illustrated 



downward flange that will overlap the edge of the unit. The cover shall be securely fastened to the unit 
and shall fit sufficiently snug to the unit to be vermin proof. The cover shall provide for watertight 
entrance of electrical cables and vent piping or air line if installed. 

17.9.3 Hand Pumps 

17.9.3.1 General 

Hand pumps shall be of the force type equipped with a packing gland around the pump rod, a delivery 
spout that is closed and downward directed, and a one-piece bell type base that is part of the pump 
stand or is attached to the pump column in a watertight manner. 

17.9.3.2 Installation 

The bell base of the pump shall be bolted with a gasket to a flange that is securely attached to the 
casing or pipe sleeve. 

17.9.4 Power Driven Pumps 

17.9.4.1 General 

The design and operating principles of each type of power driven pump determines where each may be 
located with respect to a well. The location selected for the pump determines what factors must be 
considered to make an acceptable installation. 

17.9.4.2 Location Above Well 

Any power driven pump located over a well shall be mounted on the well casing, pipe sleeve, pump 
foundation or pump stand such that a watertight closure is or can be made for the open end of the 
casing or sleeve. 

17.9.4.3 Pump Base 

The pump base bolted with a neoprene or rubber gasket or equivalent watertight seal to a foundation or 
plate provides an acceptable seal. 

17.9.4.4 Large Pump Installation 

On large pump installations, the bolting may be omitted when the weight of the pump and column is 
sufficient to make a watertight contact with the gasket. 

17.9.4.5 Pump Location Other Than Over Casing 

If the pump unit is not located over the casing or pipe sleeve, the pump delivery or suction pipes 
emerge from the top of the well, a watertight expanding rubber seal or equivalent shall be installed 
between the well casing and piping to provide a watertight closure. 

17.9.4.6 Seal Top 

The top of the seal shall not extend below the uppermost edge of the casing or pipe sleeve. 

1 7.9.5 Location in Well For Submersible Pumps 
17.9.5.1 General 

This type of location is permissible for submersible pumps only. 



2006 National Standard Plumbing Code-Illustrated 355 



17.9.5.2 Top Discharge Line 

When the discharge line leaves the well at the top of the casing, the opening between the discharge line 
and casing or pipe sleeve shall be sealed watertight with an expanding rubber seal or equivalent device. 

17.9.5.3 Underground Discharge 

When an underground discharge is desired, a properly installed pitless adapter shall be used. A check- 
valve shall be installed in the discharge line above the pump in the well. 

17.9.5.4 Top Discharge Line Sloped to Drain to Well 

When the discharge pipe leaves the well at the top, remains above ground, and slopes to drain back to 
the well, the check- valve can be located beyond the well. 

17.9.6 Offset from Well 

17.9.6.1 Location 

Pumps offset from the well, if not located in an above-ground pump house or other building, may be 
located in an approved basement provided the pump and all suction pipes are elevated at least 12 
inches above the floor. 

17.9.6.2 Buried Lines 

All portions of suction lines buried below the ground surface between the well and the pump and that 
are not enclosed in a protective pipe shall be located the same minimum distance from sources of 
contamination as are prescribed for the well in Section 16.4.3. 

17.9.6.3 Protective Pipe 

When these minimum distances cannot be obtained, the suction line shall be enclosed in a protective 
pipe of standard thickness from the well to the pump. The protective pipe shall be sealed watertight at 
both ends. This requirement shall be considered satisfied if the suction line lies within a pressure 
discharge line. 

17.10 VENTS 

17.10.1 Size 

All vent piping shall be of adequate size to allow equalization of air pressure in the well and shall not be less 
than one-half inch in diameter. 

17.10.2 Toxic or Flammable Gases 

Particular attention shall be given to proper venting of wells and pressure tanks in areas where toxic or 
flammable gases are known to be a characteristic of the water. If determined that either of these types of 
gases are present, all vents when located in buildings shall be extended to discharge outside of the building at 
a height where they will not be a hazard. 

17.10.3 VentExtension 

The vent shall extend above the upper terminal of the well with the end downturned and covered with not less 
than 16 mesh screen wire. The point of entry into the well shall be sealed watertight. 



356 2006 National Standard Plumbing Code-Illustrated 



17.11 PUMP BEARING LUBRICATION 

17.11.1 General 

Lubrication of bearings of power driven pumps shall be with water or oil that will not adversely affect the 
quality of the water to be pumped. 

17.11.2 Water Lubrication 

If a storage tank is required for the lubrication water, it shall be designed to protect the water from contami- 
nation. 

17.11.3 Oil Lubrication 

The reservoir shall be designed to protect the oil from contamination. The oil shall not contain substances that 
will cause odor or taste to the water pumped. 

17.12 WATER LEVEL MEASUREMENT 

On wells of large capacity where access for measuring the water level in the well is provided, piping for this 
purpose shall terminate above the upper well terminal, be capped or otherwise closed, and all openings around the 
piping at the point of entry into the well sealed watertight. 

17.13 PROHIBITED PUMPS 

No pitcher or chain-bucket pump shall be installed on any water supply. 

17.14 PUMP HOUSING 

17.14.1 Watertight 

A separate structure housing the water supply and pumping equipment shall have an impervious floor and 
rain-tight walls and roof. 

17.14.2 Pump Pit 

A pump pit shall be of watertight construction and provided with a positive drain or sump pump to keep the pit 
dry. 

17.15 CROSS CONNECTION 

17.15.1 Restriction 

There shall be no cross-connection between an individual water supply system and other individual or public 
water supply system. 

17.15.2 Limitations 

No water supply shall serve more than one property unless authorized by the Authority Having Jurisdiction. 



2006 National Standard Plumbing Code-Illustrated 357 



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358 



2006 National Standard Plumbing Code-Illustrated 








^ ii ^^^^^^^^^^^^^^&&a^s©i^iife^^^^^K^S 



Mobile Home & Travel Trailer Park 
Plumbing Standards 

The primary objective of this Chapter is to assure sanitary plumbing installations in trailer home parks. Reference 
should be made to the Authority Having Jurisdiction and the regulations promulgated by the Authority Having 
Jurisdiction governing the establishment and operation of trailer home parks. 

18.1 DEFINITIONS 



Comment: The requirements of this chapter are intended as general requirements for parks and 
campgrounds that serve travel trailers, recreational vehicles, and mobile homes. Travel trailers and 
recreational vehicles are used as temporary dwellings for travel or recreational purposes. Mobile 
homes are movable structures or units that are designed as living quarters. The requirements of the 
A uthority Having Jurisdiction may vary for the different types of parks and campgrounds. 



Service Buildings 

A building housing toilet, laundry and any other such facilities as may be required. 

Sewer Connection 

Sewer connection is that portion of the drainage piping that extends as a single terminal under the trailer 
coach for connection with the trailer park drainage system. 

Trailer Coach 

Any camp-car, trailer, or other vehicle with or without motive power, designed and constructed to travel on 
the public thoroughfares in accordance with provisions of the Vehicle Code and designed or used for human 
habitation. 

Trailer Coach, Dependent 

One which is not equipped with a water closet for sewage disposal. 

Trailer Coach, Independent 

One which is equipped with a water closet for sewage disposal. 

Trailer Coach Drain Connection 

The removable extension connecting the trailer coach drainage system to the trailer connection fixture. 

Trailer Coach, Left Side 

The side farthest from the curb when the trailer home is being towed or in transit. 



2006 National Standard Plumbing Code-Mummied 



359 



Trailer Connection Fixture 

A connection to a trap that is connected to the park drainage system, and receives the water, liquid or other 
waste discharge from a trailer coach. 

Trailer Park Drainage System 

The entire system of drainage piping used to convey sewage or other waste from a trailer connection fixture 
to the sewer. 

Trailer Park Branch Line 

That portion of drainage piping that receives the discharge from not more than two trailer connection fixtures. 

Trailer Park 

Any area or tract of land where space is rented or held-out for rent, or occupied by two or more trailer 
coaches. 

Trailer Park Sewer System 

That piping that extends from the public or private sewage disposal system to a point where the first trailer 
park drainage system branch fitting is installed. 

Trailer Park Water Service Main 

That portion of the water distribution system that extends from the street main, water meter, or other source 
of supply to the trailer site water service branch. 

Trailer Site 

That area set out by boundaries on which one trailer can be located. 

Trailer Site Water Service Branch 

That portion of the water distributing system extended from the park service main to a trailer site, and in- 
cludes connections, devices, and appurtenances thereto. 

Water Service Connection 

That portion of the water supply piping that extends as a single terminal under the trailer coach for connection 
with the trailer coach park water supply system. 

18.2 STANDARDS 

18.2.1 General 

Plumbing systems hereafter installed in trailer home parks shall conform to the provisions set forth in the 
preceding chapters of this Code, where applicable, and also to the provisions set forth in this Chapter. Trailer 
home park plumbing and drainage systems shall, in addition, conform to all other applicable Authority Having 
Jurisdiction regulations. 

18.2.2 Plans and Specifications 

Before any plumbing or sewerage disposal facilities are installed or altered in any trailer park, duplicate plans 
and specifications shall be filed, and proper permits obtained from the Authority Having Jurisdiction. Plans 
shall show in detail. 

360 2006 National Standard Plumbing Code-Illustrated 



18.2.2.1 Plot Plan 

Plot plan of the park, drawn to scale, indicating elevations, property lines, driveways, existing or pro- 
posed buildings, and sizes of trailer sites. 

18.2.2.2 Plumbing Layout 

Complete specifications and piping layout of proposed plumbing system or alteration. 

18.2.2.3 Sewerage Disposal Layout 

Complete specifications and piping layout of proposed sewer system or alteration. See Sections 3.4, 
3.5, 3.6, and 3.7. 

18.2.2.4 Conformance 

Trailer park plumbing system shall be designed and installed in accordance with the requirements of this 
Code and shall, in addition, conform to all other pertinent local ordinances and State regulations. 

18.2.3 Materials 

Materials shall conform to the approved standards set forth in other sections of this Code. 

18.3 SEWER 

18.3.1 Design and Installation 

The trailer park drainage system shall be designed and installed in accordance with the requirements of this 
Code. 

18.3.2 Alternate 

The trailer park drainage system may be installed by the use of a combination waste and vent drainage system 
(see Section 12.17), which shall consist of an installation of waste piping, as hereinafter provided in this 
Section, in which the traps for one or more trailer connection fixtures are not separately or independently 
vented, but which is vented through the waste piping of such size to secure free circulation of air therein. 
See Sections 12.17 for combination waste and vent systems. 

1 8.3.3 Each Independent Trailer Site 

Each independent trailer site shall be provided with a trapped trailer connection that shall consist of a three- 
inch horizontal iron pipe-size threaded connection, installed a minimum of three inches and a maximum of six 
inches (from the bottom of the connection), above the finished grade. The vertical connection to the trailer 
connection fixture shall be anchored in a concrete slab four inches thick, and 18" x 1 8" square. 

18.3.4 Above Ground 

Any part of the plumbing system extending above the ground shall be protected from damage when deemed 
necessary by the Authority Having Jurisdiction. 

18.3.5 Trap Connections 

Each trailer site shall be provided with a three-inch I.P.S. male or female threaded connection, extended 
above the surrounding grade, from a three- inch minimum size vented p-trap. 



2006 National Standard Plumbing Code-Illustrated 361 



18.3.5.1 Location 

Traps shall be located with reference to the immediate boundary lines of the designated space or area 
within each trailer site that will actually be occupied by the trailer. Each such trap shall be located in 
the rear third-quarter section along the left boundary line of the trailer parking area not less than one 
foot or more than three feet from the road side of the trailer and shall be a minimum of five feet from 
the rear boundaiy of the trailer site. This location may be varied by permission of the Authority Having 
Jurisdiction when unusual conditions are encountered. 

18.3.5.2 Material 

All traps, tail pipes, vertical vents, the upper five feet of any horizontal vent, and the first five feet of 
any trap branch shall be fabricated from materials approved for use within a building. See Sections 
3.5 and 3.6. 

18.3.6 Restriction 

No vertical pipe shall be used in a special waste and vent system, except the vent pipe, and the connection to 
the trailer connection fixture. 

18.3.7 Drain Connections 

Mobile home and travel trailer drain connections shall be of approved semi-rigid or flexible reinforced hose 
having smooth interior surfaces and not be less than a 3 -inch inside diameter. Main connections shall be 
equipped with a standard quick-disconnect screw or clamp type fitting, not smaller than the outlet. Main 
connections shall be gas-tight and no longer than necessary to make the connection between the trailer coach 
drain connection and the trailer connector fixture on the site. 

18.3.8 Cleanouts 

Cleanouts shall be provided as required by Chapter 5 of this Code, except cleanouts shall be provided in the 
vent stacks one foot above grade. 

18.3.9 Fixture Unit Loading 

For the purpose of determining pipe sizes, each trailer site connection shall be assigned a waste loading 
value of six fixture units and each trailer park drainage system shall be sized as provided in Table 18.3.12. 
Private sewage disposal shall conform to the requirements of Chapter 16 of this Code. See Table 18.3.12 
and Chapter 16. 

18.3.10 Slope 

The grade on sewers shall provide a minimum velocity of two feet per second when the pipe is flowing half 
full. See Table K-2 in Appendix K. 

18.3.11 Discharge 

The discharge of the park drainage system shall be connected to a public sewer. Where a public sewer is not 
available within 300 feet for use, an individual sewage disposal system of a type that is acceptable and 
approved by the Authority Having Jurisdiction shall be installed. 



Comment: It is preferred that trailer parks be connected to public sewers, even if more than 300 feet 
away. Trailer sites are typically densely spaced to maximize the use of the property, which leaves little 
space for an adequate on-site sewage disposal system. 



362 



2006 National Standard Plumbing Code-Illustrated 



18.3.12 Minimum Pipe Size 

Minimum pipe size of the drainage system shall be as set forth in Table 8.3.12. 



Table 18.3.12 
DRAIN PIPE SIZING 



Max. No. of Trailers, Max. No. of Trailers, 

Individually Vented Wet-Vented 



Systems Systems Size of Drain 



2 1 3" 

30 10 4" 

100 50 6" 

400 - 8 " 

1000 - 10" 



18.4 VENTING 



18.4.1 Location 



Each wet- vented drainage system shall be provided with a vent not more than 15 feet downstream from its 
upper trap, and long mains shall be provided with additional relief vents at intervals of not more than 100 feet 
thereafter. The minimum size of each vent serving a wet- vented system shall be as set forth in Table 18.4.1. 



Table 18.4.1 
VENT SIZING 



Size of Wet- Vented Drain Minimum Size of Vent 



3" 2" 

4" "5" 

5" 4" 

6" 5" 



18.4.2 Reserved 

18.4.3 Reserved 

18.4.4 Reserved 

18.4.5 Vent Connections 

All vent intersections shall be taken off above the center line of the horizontal pipe. All vent stacks shall be 
supported by a four-inch by four-inch redwood post, set in at least two feet of concrete extending at least 
four inches above the ground, or supported by another approved method. 



Comment: Treated lumber is considered to be the equivalent of redwood. 



18.4.6 Galvanized Steel Vent Pipe 

Galvanized steel vent pipe may extend below the ground vertically, and may directly intersect a drainage line 
with an approved fitting, if the entire section around both the drain and the galvanized pipe is encased in 
concrete to prevent any movement. Galvanized steel pipe encased in concrete shall be first coated with 
bituminous paint, or equivalent protective material. 



2006 National Standard Plumbing Code-Illustrated 363 



18.4.7 Location of Vent Pipes 

Vent pipes shall be located at least 10 feet above grade and 10 feet from the property line. No vent shall 
terminate directly beneath any door, window, or other ventilating openings of the building or of an adjacent 
building, nor shall any such vent terminal be within 10 feet horizontally of such opening unless it is at least 2 
feet above the top of such opening. 

18.4.8 Size of Vent Stack 

All vent stacks in the wet-vented system shall be three inches or more in diameter, except that a three-inch 
branch line may be vented by a two-inch vent. See Table 18.4.1. 

18.4.9 Branch Lines 

No three-inch branch line shall exceed six feet in length, and no four-inch branch shall exceed 1 5 feet in 
length, unless they are properly vented. 

18.4.10 Trailer Connections 

Each trailer connection fixture outlet shall be provided with a screw-type plug or cap, and be effectively 
capped when not in use. 

18.5 WATER DISTRIBUTION SYSTEM 

18.5.1 Conformance 

Each trailer park water distribution system shall conform to the requirements of Chapter 10 of this Code and 
shall be so designed and maintained as to provide a residual pressure of not less than 20 psi at each trailer site 
under normal operating conditions. (See Table 10.14.3.) Refer to Appendix B for sizing the water 
distribution systems. 

18.5.2 Individual Water Service Branch 

Every trailer site shall be provided with an individual water service branch line that shall not be less than 3/4" 
size, delivering safe, potable water. 

18.5.3 Connection Components 

A control valve shall be installed on the water service branch, followed by an approved backflow preventer in 
accordance with ASSE 1024 or CSA B64.6 on the discharge side of the control valve, with a pressure relief 
valve located on the discharge side of the backflow preventer; with a hose connection or other approved 
attachment on the trailer side of the relief valve. Each such pressure relief valve shall be equipped with a full- 
size drain with the end of the pipe not more than two feet or less than six inches above the ground and pointing 
downward. Such drain may terminate at other approved locations. No part of such drain pipe shall be trapped. 
No shut-off valve shall be installed between any such pressure relief valve and the trailer it serves. The 
backflow device and relief valve shall be located not less than 12 inches above the grade. 

18.5.4 Connection Details 

The service connection shall not be rigid. Flexible metal tubing is permitted. Fittings at either end shall be of a 
quick disconnect type not requiring any special tools or knowledge to install or remove. 

18.5.5 Water Fixture Units 

Each trailer outlet on the water distribution system shall be rated as six water fixture units. 



364 2006 National Standard Plumbing Code-Illustrated 



18.5.6 Location of Water Connection 

The trailer park water outlet for each trailer coach space shall be located near the center of the left side of 
each trailer coach. 

18.5.7 Fire Protection 

In the design of the water distribution system in a trailer park, consideration for fire outlet stations throughout 
the park should be made relative to the location and quantity of water necessary during an emergency 
period. 

18.5.8 Backflow Protection 

All requirements as described in Chapter 10 of this Code shall be considered a part of this Section. 

18.6 RESERVED 

18.7 TESTING 

Installations shall be tested and inspected as required by this Code. 

18.8 SANITARY FACILITIES 

18.8.1 Public Water Closets, Showers, and Lavatories 

Separate public water closets, showers, and lavatories shall be installed and maintained for each sex in 
accordance with the following ratio of trailer sites: 

18.8.1.1 Dependent Trailer 

Trailer parks constructed and operated exclusively for dependent trailers shall have one water closet, 
one shower, and one lavatory for each 10 sites or fractional part thereof. 



Comment: Dependent trailers are not equipped with a water closet and lavatory and are dependant on 
the trailer park for such facilities. 



18.8.1.2 Independent Trailer 

Trailer parks constructed and operated exclusively for independent trailers shall have one water closet, 
one shower, and one lavatory for each 100 sites or fractional part thereof. 



Comment: Independent trailers are equipped with a water closet and lavatory and are not dependent 
on the trailer park for such facilities. 



18.8.1.3 Combined Trailer Use 

Trailer parks constructed and operated for the combined use of dependent and independent trailers 
shall have facilities as shown in Table 18.8. 1 .3. 



2006 National Standard Plumbing Code-Illustrated 3<rr 



Table 18.8.1.3 
FACILITIES REQUIRED 


Sites 


Water Closets Showers 


Lavatories 


2-25 
26-70 


1 1 

2 2 


1 

2 



18.8.1.4 Additional Water Closets 

For combined trailer use, one additional water closet shall be provided for each 100 sites or fractional 
part thereof in excess of 70 sites. 



Comment: Section 18.8.1.4 applies to trailer parks with combined trailer use, as in Section 18.8.1.3. 



18.8.2 Exclusivity 

Each toilet facility shall be for the exclusive use of the occupants of the trailer sites in the trailer park. 

18.8.3 Showers 

In every auto and trailer park, shower bathing facilities with hot and cold running water shall be installed in 
separate compartments. Every compartment shall be provided with a self-closing door or otherwise equipped 
with a waterproof draw curtain. 

18.8.4 Laundry Facilities 

Every trailer park shall be provided with an accessory utility building containing at least one mechanical 
washing machine or laundry tray equipped with hot and cold running water for every 20 trailer sites or 
fractional part thereof, but in no case shall there be less than two laundry trays in any trailer park. 

18.8.5 Shower Compartments 

The inner face of walls of all shower compartments shall be finished with cement, concrete, metal, tile or 
other approved waterproof materials extending to a height of not less than six feet above the floor. Floors or 
shower compartments shall be made of concrete or other similar impervious material. Floors shall be water- 
proof and slope 1/4 inch per foot to the drains. 

18.9 MAINTENANCE 

All required devices or safeguards shall be maintained in good working order. The owner, operator, or lessee of 
the trailer park, or his designated agent shall be responsible for the maintenance. 

18.10 OPERATOR'S RESPONSIBILITY-VIOLATIONS 

When it is evident that there exists, or may exist, a violation of any pertinent regulation, the owner, operator, lessee, 
person in charge of the park, or any other person causing a violation shall immediately disconnect the trailer water 
supply and sewer connection from the park systems and shall employ such other corrective measures as may be 
ordered by the Authority Having Jurisdiction. 



366 2006 National Standard Plumbing Code-Illustrated 



!^---;i^jiwtw^i>^^:ir^^^i».-s,''>ifog : ?.1 




Sizing Storm 
Drainage Systems 



2006 National Standard Plumbing Code-Illustrated 



367 



A.l Rainfall Rates for Cities 

The rainfall rates in Table A.l, RAINFALL RATES FOR CITIES, are based on U.S. Weather Bureau Technical 
PaperNo. 40, specifically Chart 14: 100-YEAR 1 HOUR RAINFALL (inches) and Chart 7: 100-YEAR30-MINUTE 
RAINFALL (inches). The data in Chart 7 were multiplied by 0.72 to determine the rainfall for a 1 5-minute period, then 
multiplied by 4 to establish the corresponding rainfall rate in inches per hour. The flow rates in gallons per minute (gpm) 
were established by dividing the inches per hour by 1 2 to determine cubic feet per hour per square foot, then multiplying 
by 7.48 gallons per cubic foot to determine gallons per hour per square foot, then dividing by 60 minutes per hour to 
determine the equivalent gallons per minute. 

A.2 Roof Drainage 

Primary roof drainage systems are sized for a 1 00-year, 60-minute storm. Secondary roof drainage systems are sized 
for a more severe 100-year, 1 5-minute storm. The rainfall rates in Table A. 1 should be used for design unless higher 
rates are established locally. 

A.3 Sizing by Flow Rate 

Storm drainage systems may be sized by stormwater flow rates, using the appropriate GPM/SF of rainfall listed in 
Table A. 1 for the local area. Multiplying the listed GPM/SF by the roof area being drained (in square feet) produces 
the gallons per minute (gpm) of required flow for each drain inlet. The flow rates (gpm) can then be added to determine 
the flows in each section of the drainage system. Required pipe sizes can be determined from Table 13.6.1 and Table 
13.6.2. 

A.4 Sizing by Roof Area 

Storm drainage systems may be sized using the roof area served by each section of the drainage system. Required 
pipe sizes can be determined from Table 1 3 .6. 1 and Table 1 3 .6.2. Using this method, it may be necessary to interpolate 
between the various listed rainfall rates (inches per hour). To determine the allowable roof area for a listed size pipe 
at a listed slope, divide the allowable square feet of roof area for a 1 " rainfall rate by the listed rainfall rate for the local 
area. For example, the allowable roof area for a 6" drain at 1/8" slope with a rainfall rate of 3.2 inches/hour is 21400/ 
3.2 = 6688 square feet. 

A.5 Capacity of Rectangular Scuppers 

Table A.5 lists the discharge capacity of various width rectangular roof scuppers with various heads of water. The 
maximum allowable level of water on the roof should be obtained from the structural engineer, based on the design of 
the roof. 



2006 National Standard Plumbing Code-Illustrated 



Table A.l RAINFALL RATES FOR CITIES 





PRIMARY 


SECONDARY 




STATES AND CITIES 


STORM DRAINAGE 


STORM DRAINAGE 






60-MIN DURATION 


15-MIN DURATION 






100-YR RETURN 


100-YR RETURN 






IN/HR 


GPM/SF 


IN/HR 


GPM/SF 




ALABAMA 












Birmingham 


3.7 


0.038 


7.8 


0.081 




Huntsville 


3.3 


0.034 


7.5 


0.078 




Mobile 


4.5 


0.047 


10.1 


0.105 




Montgomery 


3.8 


0.039 


8.4 


0.087 




ALASKA 


Aleutian Islands 


1.0 


0.010 


2.5 


0.026 




Anchorage 


0.6 


0.006 


1.5 


0.016 




Bethel 


0.8 


0.008 


2.0 


0.021 




Fairbanks 


1.0 


0.010 


2.5 


0.026 




Juneau 


0.6 


0.006 


1.5 


0.016 




ARIZONA 










Flagstaff 


2.3 


0.024 


5.2 


0.054 




Phoenix 


2.2 


0.023 


4.9 


0.051 




Tucson 


3.0 


0.03 1 


5.8 


0.060 




ARKANSAS ~ 


Eudora 


3.8 


0.039 


8.6 


0.089 




Ft. Smith 


3.9 


0.041 


8.9 


0.092 




Jonesboro 


3.5 


0.036 


7.5 


0.078 




Little Rock 


3.7 


0.038 


8.6 


0.089 




CALIFORNIA 


Eureka 


1.5 


0.016 


3.7 


0.038 




Lake Tahoe 


1.3 


0.014 


2.9 


0.030 




Los Angeles 


2.0 


0.021 


4.3 


0.045 




Lucerne Valley 


2.5 


0.026 


4.3 


0.045 




Needles 


1.5 


0.016 


3.7 


0.038 




Palmdale 


3.0 


0.031 


7.2 


0.075 




Redding 


1.5 


0.016 


3.7 


0.038 




San Diego 


1.5 


0.016 


3.7 


0.038 




San Francisco 


1.5 


0.016 


3.5 


0.036 




San Luis Obispo 


1.5 


0.016 


3.7 


0.038 




COLORADO 


Craig 


1.5 


0.016 


3.5 


0.036 




Denver 


2.2 


0.023 


4.6 


0.048 




Durango 


1.8 


0.019 


4.3 


0.045 




Stratton 


3.0 


0.031 


6.6 


0.069 




CONNECTICUT 



Hartford 

New Haven 



2.8 
3.0 



0.029 
0.031 



6.6 

7.2 



0.069 
0.075 



DELAWARE 



Dover 
Rehobeth Beach 



DISTRICTOFCOLUMB1A 



3.5 
3.6 



0.036 
0.037 



7.8 
8.6 



0.081 
0.089 



Washington 



FLORIDA 



0.042 



0.089 



Daytona Beach 
Ft. Myers 
Jacksonville 
Melbourne 
Miami 
Palm Beach 
Tampa 
Tallahassee 



4.0 
4.0 
4.3 
4.0 
4.5 
5.0 
4.2 
4.1 



0.042 
0.042 
0.045 
0.042 
0.047 
0.052 
0.044 
0.043 



8.6 
10.1 

8.6 

8.6 
11.5 
11.5 
10.1 

9.2 



0.089 
0.105 
0.089 
0.089 
0.119 
0.119 
0.105 
0.096 



GEORGIA 



Atlanta 

Brunswick 

Macon 

Savannah 

Thomasville 



3.5 
4.0 
3.7 
4.0 
4.0 



0.036 
0.042 
0.038 
0.042 
0.042 



0.081 
0.089 
0.084 
0.089 
0.089 



HAWAII 



Hawaiian Islands 



(0 



2006 National Standard Plumbing Code-Illustrated 



369 



Table A.l RAINFALL RATES FOR CITIES, Continued 



STATES AND CITIES 



PRIMARY 

STORM DRAINAGE 

60-MIN DURATION 

100-YR RETURN 



IN/HR 



GPM/SF 



SECONDARY 

STORM DRAINAGE 

15-MIN DURATION 

100-YR RETURN 



IN/HR 



GPM/SF 



IDAHO 



Boise 
Idaho Falls 
Lewiston 
Twin Falls 



1.0 
1.2 

1.0 



0.010 
0.012 
0.010 
0.011 



2.3 
3.2 
2.9 
2.3 



0.024 
0.033 
0.030 
0.024 



ILLINOIS 



Chicago 
Harrisburg 
Peoria 
Springfield 



2.7 
3.1 
2.9 
3.0 



0.028 
0.032 
0.030 
0.031 



6.3 

6.9 
6.6 
6.6 



0.065 
0.072 
0.069 
0.069 



INDIANA 



Evansville 
Indianapolis 
Richmond 
South Bend 



3.0 
2.8 

2.7 
2.7 



0.031 
0.029 
0.028 
0.028 



6.9 
6.3 
6.3 
6.0 



0.072 
0.065 
0.065 
0.062 



IOWA 



Council Bluffs 
Davenport 
Des Moines 
Sioux City 



3.7 
3.0 
3.4 
3.6 



0.038 
0.031 
0.035 
0.037 



X.l 
7.2 
7.8 
7.8 



0.084 
0.075 
0.081 
0.081 



KANSAS 



Goodland 
Salina 
Topeka 
Wichita 



3.5 
3.8 
3.8 
3.9 



0.036 
0.039 
0.039 
0.041 



7.5 
8.6 
8.6 
8.9 



0.078 
0.089 
0.089 
0.092 



KENTUCKY 



Bowling Green 
Lexington 
Louisville 
Paducah 



Cheboygan 
Detroit 
Grand Rapids 
Kalamazoo 
Traverse City 



2.9 

2.9 
2.8 
3.0 



0.030 
0.030 
0.029 
0.031 



2.1 

2.5 
2.6 

2.7 
2.2 



0.022 
0.026 
0.027 
0.028 
0.023 



6.9 

6.6 
6.3 
6.9 



4.6 
5.5 
5.5 
6.0 
4.9 



0.072 
0.069 
0.065 
0.072 



LOUISIANA 


Monroe 
New Orleans 
Shreveport 


3.8 
4.5 
4.0 


0.039 
0.047 
0.042 


8.9 
10.1 
9.5 


0.092 
0.105 
0.099 


MAINE 


Bangor 
Kittery 
Millinocket 


2.2 
2.4 
2.0 


0.023 
0.025 
0.021 


4.9 

5.8 
4.3 


0.051 
0.060 
0.045 


MARYLAND 


Baltimore 
Frostburg 
Ocean City 


3.6 

2.9 
3.7 


0.037 
0.030 
0.038 


8.6 
6.6 
8.6 


0.089 
0.069 
0.089 


MASSACHUSETTS 


Adams 
Boston 
Springfield 


2.6 

2.7 
2.7 


0.027 
0.028 
0.028 


6.0 
6.3 
6.3 


0.062 
0.065 
0.065 


MICHIGAN 



0.048 
0.057 
0.057 
0.062 
0.051 



MINNESOTA 



Duluth 
Grand Forks 
Minneapolis 
Worthington 



2.6 
2.5 
3.0 

3.4 



0.027 
0.026 
0.031 
0.035 



6.0 
6.0 
6.9 

7.5 



0.062 
0.062 
0.072 
0.078 



MISSISSIPPI 



Biloxi 

Columbus 

lackson 



4.5 
3.5 
3.8 



0.047 
0.036 
0.039 



10.1 

7.8 
8.6 



0.105 
0.081 
0.089 



370 



2006 National Standard Plumbing Code-Illustrated 



Table A.l RAINFALL RATES FOR CITIES, Continued 



STATES AND CITIES 


PRIMARY 

STORM DRAINAGE 

60-MIN DURATION 

100-YR RETURN 


SECONDARY 

STORM DRAINAGE 

1S-MIN DURATION 

100-YR RETURN 




IN/HR GPM/SF 


IN/HR 


GPM/SF 


MISSOURI ■ —— — ' — - - 


Independence 
Jefferson City 
St. Louis 
Springfield 


3.7 
3.4 
3.2 
3.7 


0.038 
0.035 
0.033 
0.038 


8.4 

7.8 
7.2 
8.1 


0.87 
0.081 
0.075 

0.084 


MONTANA 










Billings 
Glendive 
Great Falls 
Missoula 


1.8 

2.5 
1.8 
1.3 


0.019 
0.026 
0.019 
0.014 


3.7 
5.8 
3.7 
2.9 


0.038 
0.060 
0.038 
0.030 


NEBRASKA '" 


Omaha 
North Platte 
Scotts Bluff 


3.6 
3.5 
2.8 


0.037 
0.036 
0.029 


8.1 
7.5 
6.0 


0.084 
0.078 
0.062 


NEVADA ~~ ~ -- ■ 


Las Vegas 

Reno 

Winnemucca 


1.5 
1.2 
1.0 


0.016 
0.012 
0.010 


3.5 
2.9 

2.3 


0.036 
0.030 
0.024 


NEW HAMPSHIRE '" " " — 


Berlin 
Manchester 


2.2 
2.5 


0.023 
0.026 


5.2 
5.S 


0.054 
0.060 


NEW JERSEY ' " " ' 


Atlantic City 

Paterson 

Trenton 


3.4 
3.0 
3.2 


0.035 
0.031 
0.033 


8.1 

6.9 

7.2 


0.084 
0.072 
0.075 


NEW MEXICO 










Albuquerque 

Carlsbad 

Gallup 


2.0 

2.6 
2.1 


0.021 
0.027 
0.022 


4.0 
6.0 
4.9 


0.042 
0.062 
0.051 


NEW YORK ~ "~ " " - 


Binghamton 
Buffalo 
New York 
Schenectady 
Syracuse 


2.4 
2.3 
3.1 

2.5 
2.4 


0.025 
0.024 
0.032 
0.026 
0.025 


5.5 
5.2 
6.9 
5.8 
5.2 


0.057 
0.054 
0.072 
0.060 
0.054 


NORTH CAROLINA " 


Ashville 
Charlotte 
Raleigh 
Wilmington 


3.2 
3.4 

4.0 
4.4 


0.033 
0.035 
0.042 
0.046 


7.2 
8.1 
8.9 
9.5 


0.075 
0.084 
0.092 

0.099 


NORTH DAKOTA 










Bismarck 

Fargo 

Minot 


2.7 
2.9 
2.6 


0.028 
0.030 
0.027 


6.3 
6.6 
5.8 


0.065 
0.069 

0.060 


OHIO ~ " 


Cincinnati 

Cleveland 

Columbus 

Toledo 

Youngstown 


2.8 

2.4 
2.7 
2.6 
2.4 


0.029 
0.025 
0.028 
0.027 
0.025 


6.3 
5.5 
6.3 
5.8 
5.8 


0.065 
0.057 
0.065 
0.060 
0.060 


OKLAHOMA 










Boise City 
Muskogee 
Oklahoma City 


3.4 

4.0 
4.1 


0.035 
0.042 
0.043 


7.8 
9.2 
9.2 


0.081 
0.096 
0.096 


OREGON 










Medford 
Portland 
Ontario 


1.3 
1.3 
1.0 


0.014 
0.014 
0.010 


3.2 
3.2 
2.3 


0.033 
0.033 
0.024 



2006 National Standard Plumbing Code-Illustrated 



371 



Table A.l RAINFALL RATES FOR CITIES, Continued 





PRIMARY 


SECONDARY 




STATES AND CITIES 


STORM DRAINAGE 


STORM DRAINAGE 






60-MIN DURATION 


15-MIN DURATION 






100-YR RETURN 


100-YR RETURN 






IN/HR 


GPM/SF 


IN/HR 


GPM/SF 




PENNSYLVANIA 


Erie 


2.4 


0.025 


5.5 


0.057 




Harrisburg 


2.9 


0.030 


6.6 


0.069 




Philadelphia 


3.2 


0.033 


7.2 


0.075 




Pittsburg 


2.5 


0.026 


5.8 


0.060 




Scranton 


2.8 


0.029 


6.0 


0.062 




RHODE ISLAND 












Newport 


3.0 


0.031 


7.2 


0.075 




Providence 


2.9 


0.030 


6.9 


0.072 




SOUTH CAROLINA 


Charleston 


4.1 


0.043 


7.8 


0.081 




Columbia 


3.5 


0.036 


8.4 


0.087 




Greenville 


3.3 


0.034 


9.2 


0.096 




SOUTH DAKOTA 












Lemmon 


2.7 


0.028 


6.3 


0.065 




Rapid City 


2.7 


0.028 


6.3 


0.065 




Sioux Falls 


3.4 


0.035 


7.5 


0.078 




TENNESSEE 












Knoxville 


3.1 


0.032 


7.2 


0.075 




Memphis 


3.5 


0.036 


7.5 


0.078 




Nashville 


3.0 


0.031 


7.2 


0.075 




TEXAS 


Corpus Christi 


4.6 


0.048 


10.7 


0.111 




Dallas 


4.2 


0.044 


9.5 


0.099 




El Paso 


2.0 


0.021 


4.9 


0.051 




Houston 


4.6 


0.048 


10.7 


0.111 




Lubbock 


3.3 


0.034 


7.5 


0.078 




San Antonio 


4.4 


0.046 


9.8 


0.102 




UTAH 












Bluff 


2.0 


0.021 


4.3 


0.045 




Cedar City 


1.5 


0.016 


3.5 


0.036 




Salt Lake City 


1.3 


0.014 


2.6 


0.027 




VERMONT 


Bennington 


2.5 


0.026 


5.8 


0.060 




Burlington 


2.3 


0.024 


5.2 


0.054 




Rutland 


2.4 


0.025 


5.5 


0.057 




VIRGINIA 












Charlottesville 


3.4 


0.035 


7.8 


0.081 




Richmond 


4.0 


0.042 


8.9 


0.092 




Roanoke 


3.3 


0.034 


7.8 


0.081 




Norfolk 


4.0 


0.042 


9.5 


0.099 




WASHINGTON 












Seattle 


1.0 


0.010 


2.3 


0.024 




Spokane 


1.0 


0.010 


2.6 


0.027 




Walla Walla 


1.0 


0.010 


2.9 


0.030 




WEST VIRGINIA 












Charleston 


2.9 


0.030 


6.6 


0.069 




Martinsburg 


3,0 


0.031 


7.2 


0.075 




Morgantown 


2.7 


0.028 


6.3 


0.065 




WISCONSIN 


La Cross 


2.9 


0.030 


6.9 


0.072 




Green Bay 


2.5 


0.026 


5.8 


0.060 




Milwaukee 


2.7 


0.028 


6.3 


0.065 




Wausau 


2.5 


0.026 


5.8 


0.60 




WYOMING 


Casper 


1.9 


0.020 


4.3 


0.045 




Cheyenne 


2.5 


0.026 


5.5 


0.057 




Evaston 


1.3 


0.014 


2.9 


0.030 




Rock Springs 


1.4 


0.015 


3.5 


0.036 





I . Rainfall rales in Hawaiian Islands vary from 1 .5 in/hr to 8.0 in/hr depending on location and elevation. Consult local data. 



372 



2006 National Standard Plumbing Code-llluslrated 



Table A.5 

DISCHARGE FROM RECTANGULAR SCUPPERS - 

GALLONS PER MINUTE 



WATER HEAD 




WIDTH OF SCUPPER 


-(Inches) 






(Inches) 


6 


12 


18 


24 


30 


36 


0.5 


6 


13 


19 


25 


32 


38 


1 


17 


35 


53 


71 


89 


107 


1.5 


31 


64 


97 


130 


163 


196 


2 




98 


149 


200 


251 


302 


2.5 




136 


207 


278 


349 


420 


3 




177 


271 


364 


458 


551 


3.5 






339 


457 


575 


693 


4 






412 


556 


700 


844 



NOTES: 



1 . Table A.5 is based on discharge over a rectangular weir with end contractions. 

2. Head is depth of water above bottom of scupper opening. 

3. Height of scupper opening should be 2 times the design head. 

4. Coordinate the allowable head of water with the structural design of the roof. 



2006 National Standard Plumbing Code-Illustrated 



373 



Blank Page 



J ' ^ 2006 National Standard Plumbing Code-illustrated 







Sizing the Building Water 
Supply System 



B.l GENERAL 377 

B.2 PRELIMINARY INFORMATION ZZZZZZZZZZZZZZZZZZZZZZ ZZZ.-ill 

B.2.1 General 3-7-7 

B.2.2 Materials for System 377 

B.2. 3 Characteristics of the Water Supply 377 

B.2.4 Location and Size of Water Supply Source 378 

B.2. 5 Developed Length of System 378 

B.2. 6 Pressure Data Relative to Source of Supply 378 

B.2. 7 Elevations 378 

B.2. 8 Minimum Pressure Required at Highest Water Outlets 378 

B.2. 9 Provision of Necessary Information on Plans 378 

B.3 DEMAND AT INDIVIDUAL OUTLETS ZZZZZZZZZZZZZ. 379 

Table B.3 MAXIMUM DEMAND AT INDIVIDUAL WATER OUTLETS 379 

B.4 RESERVED 370. 

B.5 ESTIMATING DEMAND Z'ZZZ'ZZZZZ'ZZZZZZZZZZ.380 

B.5.1 Standard Method 380 

B.5.2 Water Supply Fixture Units (WSFU) Assigned to Fixtures 380 

Table B.5.2 WATER SUPPLY FIXTURE UNITS (WSFU) AND 

MINIMUM FIXTURE BRANCH PIPE SIZES 381 

B-5.3 Table B.5.3 WATER SUPPLY FIXTURE UNITS FOR FIXTURE GROUPS '.''". 383 

Table B.5.3 BATHROOM GROUPS HAVING 1.6 GPF WATER CLOSETS OTHER 

THAN THE FLUSHOMETER VALAVE TYPE 382 

B.5.4 Demand (GPM) Corresponding to Fixture Load (WSFU) 383 

Table B.5.4 TABLE FOR ESTIMATING DEMAND... 384 

B.5. 5 Total Demand Including Continuous Flow 383 

B.6 LIMITATION OF VELOCITY ZZZZZZ.3&4 

B.6.1 Consideration of Velocity in Design 384 

B.6.2 Good Engineering Practice 385 

B.6. 3 Manufacturers' Recommendations for Avoiding Erosion/Corrosion 385 

B.7 SIMPLIFIED METHOD FOR SIZING SYSTEMS IN RELATIVELY LOW BUILDINGS ZZZZZZZ. 385 

B.7.1 Application 385 

B.7.2 Simplified Method Based on Velocity Limitations 386 

B.7. 3 Sizing Tables Based on Velocity Limitations 386 

Table B.7.3.A - GALVANIZED STEEL PIPE - STD WT ZZZZ1 387 

Table B.7.3.B - TYPE K COPPER TUBE 387 

Table B.7.3.C - TYPE L COPPER TUBE 388 

Table B.7.3.D - TYPE M COPPER TUBE .' 388 

Table B.7.3.E - CPVC, PVC, ABS PLASTIC PIPE - SCHEDULE 40 389 

Table B.7.3.F - CPVC, PVC, ABS PLASTIC PIPE - SCHEDULE 80 389 

Table B.7.3.G - CPVC PLASTIC TUBING (Copper Tube Size - SDR 1 1 389 

B.7.4 Step-by-Step Procedure of Simplified Sizing Method 386 



2006 National Standard Plumbing Code-Illustrated 375 



B.8 ILLUSTRATION OF SIMPLIFIED SIZING METHOD APPLICATION 390 

B.8.I Example 390 

Figure B.8. 1 WATER PIPING ISOMETRIC (NO SCALE) 391 

DATA for FIGURE B.8.1 - WATER SUPPLY FIXTURE UNITS (WSFU) 392 

B.8.2 Solution 390 

B.8.3 Supplementary Check of Friction Loss in Main Lines and Risers 395 

Figure B.8.2 WATER PIPING ISOMETRIC (NO SCALE) 393 

Table B.8.2 PRESSURE DROPS IN THE BASIC DESIGN CIRCUIT IN FIGURE B.8.2 394 

B.8.4 Application to Systems in High Buildings 395 

B.9 LIMITATION OF FRICTION 395 

B.9.1 Basic Criterion 395 

B.9.2 Maximum Permissible Friction Loss 395 

B.9.3 Basic Design Circuit 396 

B.9.4 Friction Loss in Equipment 396 

B.9. 5 Estimating Pressure Loss in Displacement Type Cold-Water Meters 396 

B.9.6 Uniform Pipe Friction Loss 397 

B.9.7 Equivalent Length of Piping 397 

Table B.9.7A ALLOWANCE IN EQUIVALENT LENGTH OF 
PIPE FOR FRICTION LOSS IN VALVES AND 

THREADED FITTINGS (NPT Sizes) 397 

Table B.9.7B ALLOWANCE IN EQUIVALENT LENGTH OF 
TUBE FOR FRICTION LOSS IN VALVES AND 

FITTINGS (Copper Tubing) 398 

Table B.9.7.C EQUIVALENT LENGTH OF PIPE FOR FRICTION LOSS 

IN SCHEDULE 40 CPVC FITTINGS 398 

Table B.9.7.D EQUIVALENT LENGTH OF PIPE FOR FRICTION LOSS 

IN SCHEDULE 80 CPVC FITTINGS 398 

Table B.9.7.E EQUIVALENT LENGTH OF PIPE FOR FRICTION LOSS 

IN CPVC SDR 1 1 CTS TUBING FITTINGS 398 

B.9. 8 Determination of Flow Rates Corresponding to Uniform Pipe Friction Loss 397 

B.9.8.1 Flow vs. Pressure Drop - Galvanized Steel ASTM A53 400 

B.9. 8. 2 Flow vs. Pressure Drop - Type K Copper Tube 401 

B.9. 8. 3 Flow vs. Pressure Drop - Type L Copper Tube 402 

B.9. 8. 4 Flow vs. Pressure Drop - Type M Copper Tube 403 

B.9. 8. 5 Flow vs. Pressure Drop - CPVC/PVC/ABS Sched 40 Pipe 404 

B.9.8.6 Flow vs. Pressure Drop - CPVC/PVC/ABS Sched 80 Pipe 405 

B.9.8.7 Flow vs. Pressure Drop - CPVC Tubing (Copper Tube Size SDR1 1) 406 

B.10 DETAILED SIZING METHOD FOR SYSTEMS IN BUILDINGS 

OF ANY HEIGHT 399 

B.ll ILLUSTRATION OF DETAILED SIZING METHOD APPLICATION 407 

B.ll.l Example 407 

B.11.2 Solution 407 

Table B. 11.2 TYPE L COPPER TUBING FOR "FAIRLY SMOOTH" CONDITION 408 

B.12 MANIFOLD TYPE PARALLEL WATER DISTRIBUTION SYSTEMS 408 

B.12.1 Manifolds 408 

Table B.12. 1 MANIFOLD SIZING 409 

B.12.2 Distribution Lines 409 



376 2006 National Standard Plumbing Code-Illustrated 



B.l GENERAL 

Note that there are two questions regarding water supply to a building: first, total consumption of water (hot or cold 
or both) over a period of time, or second, peak flow at any instant of time. This appendix considers only the second 
question. J 

Proper design of the water-distributing system in a building is necessary to avoid excessive installed cost and in 
order that the various fixtures may function properly under normal conditions. The instantaneous flow of either hot 
or cold water in any building is variable, depending on the type of structure, usage, occupancy, and time of day 
The correct design results in piping, water heating, and storage facilities of sufficient capacity to meet the probable 
peak demand without wasteful excess in either piping or maintenance cost. 
For additional information on this subject, the reader is referred to: 

National Bureau of Standards Building Materials and Structures Report BMS 65 (1940), Methods of Estimating 
Loads in Plumbing Systems, by R. B. Hunter 

National Bureau of Standards Building Materials and Structures Report BMS 79 (1941), Water-Distributing 
Systems for Buildings, by R. B. Hunter 

New York State Division of Housing and Community Renewal Building Codes Bureau Technical Report No 1 
(1 964), A Simplified Method for Checking Sizes of Building Water Supply Systems, by Louis S. Nielsen. 

B.2 PRELIMINARY INFORMATION 

B.2.1 General 

The information necessary for sizing the building water supply system is described in B.2.2 through B.2.9. 
Correct sizing is contingent upon accuracy and reliability of the information applied. Thus, such information 
should be obtained from responsible parties and appropriate local authorities recognized as sources of the 
necessary information. 

B.2.2 Materials for System 

Determine what kind or kinds of piping materials are to be installed in the system. This is a matter of selection 
by the owner of the building or his authorized representative, who may be the architect, engineer, or contrac- 
tor, as the case may be. 

B.2.3 Characteristics of the Water Supply 

The coirosivity and the scale-forming tendency of a given water supply with respect to various kinds of piping 
materials is information that most officials, architects, engineers, and contractors in a water district normally 
have at their fingertips, as a result of years of experience. For anyone without such experience and knowl- 
edge, significant characteristics of the water supply, such as its pH value, CO, content, dissolved air content, 
carbonate hardness, Langelier Index, and Ryznar Index, may be applied to indicate its coirosivity and 
scale-forming tendency. The most appropriate source of such information is the local water authority having 
jurisdiction over the system supplying the water, or over the wells from which water is pumped from the 
underground water table. 



2006 National Standard Plumbing Code-Illustrated *** , 7? 



B.2.4 Location and Size of Water Supply Source 

Location and size of the public water main, where available, should be obtained from the local water author- 
ity. Where a private water supply source, such as a private well system, is to be used, the location and size as 
designed for the premises should be determined. 

B.2.5 Developed Length of System 

Information should be obtained regarding the developed length of the piping run from the source of water 
supply to the service control valve of the building (i.e., the developed length of the water service pipe as 
shown on site plans). Also, determine the developed length of the piping run from the service control valve to 
the highest and/or the most remote water outlet on the system. This may be established by measurement of 
the piping run on the plans of the system. 

B.2.6 Pressure Data Relative to Source of Supply 

Maximum and minimum pressures available in the public main at all times should be obtained from the water 
authority, as it is the best source of accurate and reliable infonnation on this subject. 

Where a private well water supply system is to be used, the maximum and minimum pressures at which it will 
be adjusted to operate may be applied as appropriate in such cases. 

B.2.7 Elevations 

The relative elevations of the source of water supply and the highest water supply outlets to be supplied in the 
building must be determined. In the case of a public main, the elevation of the point where the water service 
connection is to be made to the public main should be obtained from the local water authority. It has the most 
authoritative record of elevations of the various parts of the public system, and such elevations are generally 
referred to a datum as the reference level, usually related to curb levels established for streets. 

Elevation of the curb level directly in front of the building should be obtained from building plans, as such 
information is required to be shown on the building site plans. Elevations of each floor on which fixtures are to 
be supplied also may be determined from the building plans. 

B.2.8 Minimum Pressure Required at Water Outlets 

Information regarding the minimum flowing pressure required at water outlets for adequate, normal flow 
conditions consistent with satisfactory fixture usage and equipment function may be deemed to be as follows: 
15 psig flowing for all water supply outlets at common plumbing fixtures, except 20 psig for flushometer 
valves on siphon jet water closets and 25 psig for flushometer valves for blowout water closets and blowout 
urinals. Flushometer tank (pressure assisted) water closets require a minimum of 25 psig static pressure. For 
other types of water supplied equipment, the minimum flow pressure required should be obtained from the 
manufacturer. 

B.2.9 Provision of Necessary Information on Plans 

The basis for designing sizes of water supply piping should be provided on plans of the water supply system 
when submitted to plumbing plan examiners for proposed installations. Provision of such information permits 
the examiner to quickly and efficiently check the adequacy of sizes proposed for the various parts of the 
building water supply system. 



37g 2006 National Standard Plumbing Code-Illustrated 



B.3 DEMAND AT INDIVIDUAL OUTLETS 

Maximum possible flow rates at individual fixtures and water outlets have become generally accepted as industry 
practice, which have since become maximum rates set by law. Recognized flow rates at individual water outlets 
for various types of typical plumbing fixtures and hose connections are given in Table B.3. 
For older faucets, if the applied pressure is more than twice the minimum pressure required for satisfactory water 
supply conditions, an excessively high discharge rate may occur. Such rates may cause the actual flow in the 
piping to exceed greatly the estimated probable peak demand rate determined in accordance with the standard 
method discussed in Section B.5. Such excessive velocity of flow and friction loss in piping may adversely affect 
performance and durability of the system. 

More recent faucets, however, are equipped with flow limiting devices that control the discharge rate at a nearly 
constant value over a large range of pressures. 

Where necessary, it is recommended that means to control the rate of supply should be provided in the fixture 
supply pipe (or otherwise) wherever the available pressure at an outlet is more than twice the minimum pressure 
required for satisfactory supply. For this purpose, individual regulating valves, variable orifice flow control devices, 
or fixed orifices may be provided. They should be designed or adjusted to control the rate of supply to be equal to 
or less than the maximum rates set by law. 



Table B.3 

MAXIMUM DEMAND AT INDIVIDUAL WATER OUTLETS 



Type of Outlet Maximum Demand, (gpm) 



Metering lavatory faucet 0.25 gal/cycle 

Self-closing lavatory faucet 0.5 

Drinking fountain jet 0.75 

Ordinary lavatory faucet 2.5 

Shower head, 1/2" 2.5 

Laundry faucet, 1/2" 2.5 

Ballcock in water closet flush tank 3.0 

Dishwashing machine (domestic) 4.0 

Laundry machine (8 or 16 lbs.) 4.0 

Sink faucet, 3/8" or 1/2" 4.5 

Bath faucet, 1/2" 5.0 

Hose bibb or sillcock (1/2") 5.0 

Sink faucet, 3/4" 6.0 

1/2" flush valve (15 psi flow pressure) 15.0 

1 " flush valve ( 1 5 psi flow pressure) 27.0 

1 " flush valve (25 psi flow pressure) 35.0 



B.4 RESERVED 



2006 National Standard Plumbing Code-Illustrated 379 



B.5 ESTIMATING DEMAND 

B.5.1 Standard Method 

A standard method for estimating the maximum probable demand in building water supply systems has 
evolved and become recognized as generally acceptable. In 1923, the fixture unit method of weighting fixtures 
in accordance with their load-producing effects was proposed by Roy B. Hunter, of the National Bureau of 
Standards. After studying application of the method in the design of federal buildings over a period of years, 
the method was revised by Hunter in 1940 1 , and then recommended for general application. With appropriate 
modifications recently made for modern fixtures, the method fills the need for a reliable, rational way to 
estimate probable peak demand in water supply systems for all types of building occupancy. 

Note that the concept of maximum probable demand is one of probability. We are saying, in effect, that 
the calculated flow rate at any point in a water piping system will not be exceeded more than, say, 0.1% of 
the time. For most systems designed by the method described herein, the design flow rates are never 
reached. Therefore, the method gives a conservative approach that still does not result in wasteful oversizing. 

B.5.2 Water Supply Fixture Units (WSFU) Assigned to Fixtures 

Individual fixture branch piping should be sized to provide the flow rates listed in Table B.3 for the particular 
fixture. Minimum fixture branch pipe sizes are listed in Table B.5.2. 

Peak demand in building water supply systems serving multiple fixtures cannot be determined exactly. The 
demand imposed on a system by intermittently used fixtures is related to the number, type, time between uses, 
and probable number of simultaneous uses of the fixtures installed in the building. In the standard method, 
fixtures using water intermittently under several conditions of service are assigned specific load values in 
terms of water supply fixture units. The water supply fixture unit (WSFU) is a factor so chosen that the load- 
producing effects of different kinds of fixtures under their conditions of service can be expressed approxi- 
mately as multiples of that factor. WSFUs for two or more fixtures can then be added to determine their 
combined effect on the water supply system. 

Values assigned to different kinds of fixtures and different types of occupancies are shown in Table B.5.2. 
The total WSFUs represent the fixture's demand on the domestic water service to the building. For fixtures 
having both hot and cold water supplies, the values for separate hot and cold water demands are taken as 
being three-quarters (3/4) of the total value assigned to the fixture in each case, rounded to the nearest tenth 
of a WSFU. As an example, since the value assigned to a kitchen sink in an individual dwelling unit is 1 .5 
WSFU, the separate demands on the hot and cold water piping thereto are taken as being 1 . 1 WSFU. 

Another consideration, added in 1994, is the nature of the application of the plumbing fixture. Table B.5.2 
includes columns for Individual Dwelling Units, More Than 3 Dwelling Units, Other Than Dwelling Units, and 
Heavy-Use Assembly. The concept behind these added classifications is that the maximum probable demand 
created by plumbing fixtures varies depending on the type of occupancy in which they are installed. 



1. National Bureau of Standards Building Materials and Structures Report BMS 6, Methods of Estimating Loads in Plumbing Systems, by R. B. Hunter. 



380 



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382 



2006 National Standard Plumbing Code-Illustrated 



B.5.3 Water Supply FixtureUnits for Fixture Groups 

Table B.5.3 lists water supply fixture unit values for typical groups of fixtures in bathrooms, kitchens, and 
laundries in dwelling units. There is more diversity in the use of the fixtures in these groups than is reflected 
by WSFU values for the individual fixtures. The "Total WSFU" represents the demand that the group places 
on the domestic water service to the building. The separate cold and hot WSFU's for the group are each 
taken as % of the WSFU values for the individual fixtures in the group according to Table B.5.3, but not 
greater than the "Total WSFU" for the group. An exception is that the hot WSFU values for bathroom groups 
having 3.5 GPF (or greater) water closets are the same as those having 1.6 GPF water closets, since the hot 
WSFU's are not affected by the demand of the water closet. 

B.5.4 Demand (GPM) Corresponding to Fixture Load (WSFU) 

To determine the maximum probable demand in gallons per minute corresponding to any given load in water 
supply fixture units, reference should be made to Table B.5.4, in which the values have been arranged for 
convenient conversion of maximum probable demand from terms of water supply fixture units of toad to 
gallons per minute of flow. Intermediate values may be interpolated for loads between those shown in Table 
B.5.4. 

Note in the table that the maximum probable demand corresponding to a given number of water supply fixture 
units is generally much higher for a system in which water closets are flushed by means of direct-supply 
flushometer valves than for a system in which the water closets are flushed by other types of flushing de- 
vices. The difference in maximum probable demand between the two systems diminishes as the total number 
of fixture units of load rises. At 1,000 water supply fixture units, the maximum probable demand in both types 
of systems is the same, 2 1 gpm. 

Where a part of the system does not supply flushometer water closets, such as in the case with hot water 
supply piping and some cold water supply branches, the maximum probable demand corresponding to a given 
number of water supply fixture units may be determined from the values given for a system in which water 
closets are flushed by flush tanks. 

B.5.5 Total Demand Including Continuous Flow 

To estimate the maximum probable demand in gpm in any given water supply pipe that supplies outlets at 
which demand is intermittent and also outlets at which demand is continuous, the demand for outlets that pose 
continuous demand during peak periods should be calculated separately and added to the maximum probable 
demand for plumbing fixtures used intermittently. Examples of outlets that impose continuous demand are 
those for watering gardens, washing sidewalks, irrigating lawns, and for air conditioning or refrigeration 
apparatus. 

Note that some continuous-flow outlets may be controlled to be used only during low-flow periods in the 
system. Such time-controlled loads should not be added to the maximum probable demand for intermittently 
used fixtures, since they will not occur at the same times. In such cases, it will be necessary to consider both 
situations and size the piping for the worse case. 



2006 National Standard Plumbing Code-Illustrated 



383 



Table B.5.4 
TABLE FOR CONVERTING DEMAND IN WSFU TO GPM 1 



WSFU 


GPM 

FlushTanks 2 


GPM 
FlushValves 3 


WSFU 


GPM 
FlushTanks 2 


GPM 
FlushValves 3 


3 


3 




120 


49 


74 


4 


4 




140 


53 


78 


5 


4.5 


22 


160 


57 


83 


6 


5 


23 


180 


61 


87 


7 


6 


24 


200 


65 


91 


8 


7 


25 


225 


70 


95 


9 


7.5 


26 


250 


75 


100 


10 


8 


27 


300 


85 


110 


11 


8.5 


28 


400 


105 


125 


12 


9 


29 


500 


125 


140 


13 


10 


29.5 


750 


170 


175 


1.4 


10.5 


30 


1000 


210 


210 


15 


11 


31 


1250 


240 


240 


16 


12 


32 


1500 


270 


270 


17 


12.5 


33 


1750 


300 


300 


18 


13 


33.5 


2000 


325 


325 


19 


13.5 


34 


2500 


380 


380 


20 


14 


35 


3000 


435 


435 


25 


17 


38 


4000 


525 


525 


30 


20 


41 


5000 


600 


600 


40 


25 


47 


6000 


650 


650 


50 


29 


51 


7000 


700 


700 


60 


33 


55 


8000 


730 


730 


80 


39 


62 


9000 


760 


760 


100 


44 


68 


10,000 


790 


790 



NOTES: I . This table converts water supply demands in water supply fixture units (WSFU) to required water flow in gallons per minute 
(GPM) for the purpose of pipe sizing. 

2. This column applies to the following portions of piping systems: 
(a). Hot water piping; 

(b). Cold water piping that serves no water closets; and 
(c). Cold water piping that serves water closets other than flush valve type. 

3. This column applies to portions of piping systems where the water closets are the flush valve type. 



B.6 LIMITATION OF VELOCITY 

B.6.1 Consideration of Velocity in Design 

Velocity of flow through water supply piping during periods of peak demand is an important factor that must be 
considered in the design of building water supply systems. Limitation of water velocity should be observed in order 
to avoid objectionable noise effects in systems, shock damage to piping, equipment, tanks, coils, and joints, and 
accelerated deterioration and eventual failure of piping from corrosion. (Also see Section 10.14.1) 



384 



2006 National Standard Plumbing Code-Illustrated 



B.6.2 Good Engineering Practice 

In accordance with good engineering practice, it is recommended generally that maximum velocity at maxi- 
mum probable demand in supply piping be limited to 8 fps. This is deemed essential in order to avoid such 
objectionable effects as the production of whistling line noise, the occurrence of cavitation, and associated 
excessive noise in fittings and valves. 

Note that this velocity is too great for systems where the flow is continuous, as in the case of recirculated hot 
water piping. The continuous flow rate for hot water with modest chemical content should be limited to not 
more than 2 fps for such continuous systems. That is, verify that the flow rate in the system as a result of the 
circulation pump only does not exceed 2 fps at any point. 

It is also recommended that maximum velocity be limited to 4 fps in water supply piping that supply a 
quick-closing device, such as a solenoid valve, pneumatic valve, or a quick-closing valve or faucet of the self- 
closing, push-pull, push-button, or other similar type. This limitation is necessary in order to avoid excessive 
and damaging shock pressures in the piping and equipment when flow is suddenly shut off. Plumbing equip- 
ment and systems are not designed to withstand the very high shock pressures that may occur as the result of 
sudden cessation of high velocity flow in piping. (Also see Section 10.14.1) 

B.6.3 Manufacturers' Recommendations for Avoiding Erosion/Corrosion 

Velocity limits recommended by pipe manufacturers to avoid accelerated deterioration of their piping materi- 
als due to erosion/corrosion should be observed. Recent research studies have shown that turbulence accom- 
panying even relatively low flow velocities is an important factor in causing erosion/corrosion, and that this is 
especially likely to occur where the water supply has a high carbon dioxide content (i.e., in excess of 10 ppm), 
and where it has been softened to zero hardness. Another important factor is elevated water temperature 
(i.e., in excess of 1 10°F). 

To control erosion/corrosion effects in copper water tube, and copper and brass pipe, pipe manufacturers' 
recommendations are as follows: 

(1) Where the water supply has a pH value higher than 6.9 and a positive scale-forming tendency, such as 
may be shown by a positive Langelier Index, peak velocity should be limited to 8 fps; 

(2) Where the water supply has a pH value lower than 6.9 and may be classified as aggressively corro- 
sive, or where the water supply has been softened to zero hardness by passage through a water softener, 
peak velocity should be limited to 4 fps; and 

(3) The velocity in copper tube conveying hot water at up to 140°F should be limited to 5 fps because of 
the accelerated corrosion rate with hot water. Velocities should be limited to 2 - 3 fps for temperatures 
above 140° F. 

Note that the above values apply to velocities at maximum probable demand. For continous flow circulating 
systems, do not exceed 2 fps flow rate for the flow produced by the circulator. 

B.7 SIMPLIFIED METHOD FOR SIZING SYSTEMS IN 
RELATIVELY LOW BUILDINGS 

B.7.1 Application 

A simplified method for sizing building water supply systems in accordance with the maximum probable 
demand load, in terms of water supply fixture units, has been found to constitute a complete and proper 
method for adequately sizing the water supply systems of a specific category of buildings. In this category are 



2006 National Standard Plumbing Code-Illustrated ^85 



all buildings supplied from a source at which the minimum available water pressure is adequate for supplying 
the highest and most remote fixtures satisfactorily during peak demand. Included are almost all one- and 
two-family dwellings, most multiple dwellings up to at least three stories in height, and a considerable portion 
of commercial and industrial buildings of limited height and area, when supplied from a source at which the 
minimum available pressure is not less than 50 psi. Under such conditions, the available pressure generally is 
more than enough for overcoming static head and ordinary pipe friction losses, so that pipe friction is not an 
additional factor to consider in sizing. 

B.7.2 Simplified Method Based on Velocity Limitations 

This method is based solely on the application of velocity limitations that are: 

(1) Recognized as good engineering practice; and 

(2) Authoritative recommendations issued by manufacturers of piping materials regarding proper use of 
their products in order to achieve durable performance and avoid failure in service, especially in water areas 
where the supply is aggressively corrosive. These limitations have been detailed in Section B.6. (Also see 
Section 10.14.1.) 

B.7.3 Sizing Tables Based on Velocity Limitations 

Tables B.7.3.A through G provide a means of sizing water supply piping on the basis of flow velocities ranging 
from 4 fps to 8 fps. The velocity in copper water tube for hot water up to 140°F should not exceed 5 fps. The 
water flow rates, flow velocities, and pressure loss rates are based on Tables B. 9.8.1 through B.9.8.7 for the 
various piping materials. The allowable water supply fixture unit (WSFU) fixture loadings are based on Table 

B.5.4. 

The pressure loss data in the B.7.3 tables is based on friction for straight pipe and tube and does not include 
allowances for fittings, valves, and appurtenances. The equivalent length of the piping can be determined by 
adding the equivalent length of fittings and valves in Tables B.9.7.A, B, C, D, and E. If the exact layout of the 
piping systems cannot be determined, allowances for fittings and valves range up to 50% of the pipe length for 
smooth bore piping such as copper and solvent cement joint plastic piping and up to 75% of the pipe length for 
steel and plastic piping with threaded joints. 

In Tables B.7.3 .A through B.7.3 .G, the columns headed "WSFU (tanks)" apply to piping that serves water closets 
having gravity or pressure-type flush tanks and no fixtures that are flushed by flushometer valves. The columns 
headed "WSFU (valves)" apply to piping that serves fixtures that are flushed by flushometer valves. 

B.7.4 Step-by-Step Procedure of Simplified Sizing Method 

For sizing systems in relatively low buildings, the simplified sizing method consists of the following seven 
steps: 

1 . Obtain all information necessary for sizing the system. Such information should be obtained from 
responsible parties and appropriate local authorities recognized as sources of the necessary information. (See 
Section B.2.) 

2. Provide a schematic elevation of the complete water supply system. Show all piping connections in 
proper sequence and all fixture supplies. Identify all fixtures and risers by means of appropriate letters, 
numbers, or combinations thereof. Identify all piping conveying water at a temperature above 150°F, and all 
branch piping to such water outlets as solenoid valves, pneumatic valves, or quick-closing valves or faucets. 
Provide on the schematic elevation all the necessary information obtained in Step 1. (See Section B.2.9.) 

3. Mark on the schematic elevation, for each section of the complete system, the hot and cold water loads 
conveyed thereby in terms of water supply fixture units in accordance with Table B.5.2. 



386 



2006 National Standard Plumbing Code-Illustrated 



Table B.7.3.A GALVANIZED STEEL PIPE - STD WT 
WATER FLOW VELOCITY 


PIPE 

SIZE 


4FPS 


8FPS 


PIPE 
SIZE 


WSFU 
(tanks) 


WSFU 

(valves) 


FLOW 
GMP 


PD 
psi/ 100ft 


WSFU 
(tanks) 


WSFU 
(valves) 


FLOW 
GMP 


PD 

psi/ 100ft 


1/2" 


4 




3.8 


7.6 


9 




7.6 


27.3 


1/2" 


3/4" 


8 




6.6 


5.5 


19 




13.3 


19.7 


3/4" 


I" 


15 




10.8 


4.1 


33 


5 


21.5 


14.9 


1" 


1-1/4" 


28 




18.6 


3.0 


74 


24 


37.3 


10.8 


1-1/4" 


1-1/2" 


41 


8 


25.4 


2.5 


129 


49 


50.8 


9.1 


1-1/2" 


2" 


91 


31 


41.8 


1.9 


293 


163 


83.7 


6.8 


2" 


2-1/2" 


174 


73 


59.7 


1.5 


472 


363 


119.4 


5.5 


2-1/2" 


3" 


336 


207 


92.2 


1.2 


840 


817 


184.4 


4.3 


3" 


4" 


687 


634 


158.7 


0.9 


1925 


1925 


317.5 


3.1 


4" 


5" 


1329 


1329 


249.4 


0.7 


3710 


3710 


498.9 


2.4 


5" 


6" 


2320 


2320 


360.2 


0.5 


7681 


7681 


720.4 


1.9 


6" 



Table B.7.3.B - TYPE K COPPER TUBE 
WATER FLOW VELOCITY 


TUBE 
SIZE 


4FPS 


5FPS 


8FPS 


TUBE 
SIZE 


WSFU 
(tanks) 


WSFU 
(valves) 


FLOW 
GPM 


PD 

psi/ 100ft 


WSFU 
(tanks) 


WSFU 
(valves) 


FLOW 
GPM 


PD 

psi/ 100ft 


WSFU 
(tanks) 


WSFU 
(valves) 


FLOW 
GPM 


PD 

psi/IOOft 


3/8" 






1.6 


8.4 






2.0 


12.7 


3 




3.2 


30.4 


3/8" 


1/2" 






2.7 


6.1 


3 




3.4 


9.3 


6 




5.4 


22.1 


1/2" 


3/4" 


6 




5.4 


4.1 


8 




6.8 


6.2 


15 




10.9 


14.8 


3/4" 


1" 


13 




9.7 


2.9 


16 




12.1 


4.4 


29 




19.4 


10.6 


1" 


1-1/4" 


22 




15.2 


2.3 


28 




19.0 


3.4 


53 


14 


30.4 


8.1 


1-1/4" 


1-1/2" 


33 


5 


21.5 


1.8 


45 


10 


26.9 


2.8 


96 


33 


43.0 


6.7 


1-1/2" 


2" 


75 


24 


37.6 


1.3 


112 


40 


47.0 


2.0 


251 


126 


75.2 


4.8 


2" 


2-1/2" 


165 


69 


58.1 


1.0 


238 


115 


72.6 


1.6 


456 


341 


116.1 


3.7 


2-1/2" 


3" 


289 


159 


82.8 


0.8 


392 


267 


103.4 


1.3 


725 


682 


165.5 


3.0 


3" 


4" 


615 


541 


145.7 


0.6 


826 


801 


182.1 


0.9 


1678 


1678 


291.4 


2.2 


4" 


5" 


1134 


1134 


226.1 


0.5 


1605 


1605 


282.6 


0.7 


3191 


3191 


452.2 


1.7 


5" 


6" 


1978 


1978 


322.8 


0.4 


2713 


2713 


403.5 


0.6 


5910 


5910 


645.5 


1.4 


6" 



2006 National Standard Plumbing Code-Illustrated 



387 



Table B.7.3.C - TYPE L COPPER TUBE 
WATER FLOW VELOCITY 


TUBE 
SIZE 


4FPS 


5FPS 


8FPS 


TUBE 
SIZE 


WSFU 
(tanks) 


WSFU 
(valves) 


FLOW 
GPM 


PD 

psi/lOOft 


WSFU 
(tanks) 


WSFU 
(valves) 


FLOW 
GPM 


PD 

psi/lOOft 


WSFU 
(tanks) 


WSFU 
(valves) 


FLOW 
GPM 


PD 

psi/lOOft 


3/8" 






1.8 


7.8 


2 




2.3 


11.7 


4 




3.6 


28.0 


3/8" 


1/2" 


3 




2.9 


5.9 


4 




3.6 


8.9 


7 




5.8 


21.3 


1/2" 


3/4" 


7 




6.0 


3.9 


9 




7.5 


5.8 


16 




12.1 


13.9 


3/4" 


1" 


14 




10.3 


2.8 


18 




12.9 


4.3 


31 




20.6 


10.2 


1" 


1-1/4" 


23 




15.7 


2.2 


29 




19.5 


3.3 


56 


15 


31.3 


8.0 


1-1/4" 


1-1/2" 


34 


5 


22.2 


1.8 


47 


11 


27.7 


2.7 


101 


36 


44.4 


6.5 


1-1/2" 


2" 


79 


26 


38.6 


1.3 


117 


43 


48.2 


2.0 


261 


136 


77.2 


4.7 


2" 


2-1/2" 


173 


73 


59.5 


1.0 


247 


120 


74.4 


1.5 


470 


360 


119.0 


3.7 


2-1/2" 


3" 


300 


170 


84.9 


0.8 


406 


281 


106.2 


1.3 


749 


713 


169.9 


3.0 


3" 


4" 


635 


567 


149.3 


0.6 


854 


833 


186.7 


0.9 


1739 


1739 


298.7 


2.2 


4" 


5" 


1189 


1189 


232.7 


0.5 


1674 


1674 


290.9 


0.7 


3338 


3338 


465.5 


1.7 


5" 


6" 


2087 


2087 


334.6 


0.4 


2847 


2847 


418.2 


0.6 


6382 


6382 


669.1 


1.4 


6" 



Table B.7.3.D - TYPE M COPPER TUBE 
WATER FLOW VELOCITY 


TUBE 
SIZE 


4FPS 


5FPS 


8FPS 


TUBE 
SIZE 


WSFU 
(tanks) 


WSFU 
(valves) 


FLOW 
GPM 


PD 

psi/lOOft 


WSFU 
(tanks) 


WSFU 
(valves) 


FLOW 
GPM 


PD 

psi/ 100ft 


WSFU 
(tanks) 


WSFU 
(valves) 


FLOW 
GPM 


PD 

psi/lOOft 


3/8" 






2.0 


7.3 






2.5 


11.1 


4 




4.0 


26.6 


3/8" 


1/2" 


3 




3.2 


5.6 


4 




4.0 


8.5 


7 




6.3 


20.2 


1/2" 


3/4" 


7 




6.4 


3.7 


10 




8.1 


5.6 


18 




12.9 


13.4 


3/4" 


1" 


15 




10.9 


2.7 


19 




13.6 


4.1 


34 


5 


21.8 


9.9 


1" 


1-1/4" 


24 




16.3 


2.2 


30 




20.4 


3.3 


59 


17 


32.6 


7.8 


1-1/4" 


1-1/2" 


36 


6 


22.8 


1.8 


49 


12 


28.5 


2.7 


107 


38 


45.7 


6.4 


1-1/2" 


2" 


82 


28 


39.5 


1.3 


122 


46 


49.4 


2.0 


270 


144 


79.1 


4.7 


2" 


2-1/2" 


180 


77 


61.0 


1.0 


256 


131 


76.2 


1.5 


485 


380 


121.9 


3.6 


2-1/2" 


3" 


310 


180 


87.0 


0.8 


419 


294 


108.8 


1.2 


775 


743 


174.0 


3.0 


3" 


4" 


648 


583 


151.6 


0.6 


872 


854 


189.5 


0.9 


1783 


1783 


303.3 


2.1 


4" 


5" 


1215 


1215 


235.8 


0.5 


1706 


1706 


294.8 


0.7 


3407 


3407 


471.6 


1.7 


5" 


6" 


2125 


2125 


338.7 


0.4 


2894 


2894 


423.4 


0.6 


6548 


6548 


677.4 


1.3 


6" 



388 



2006 National Standard Plumbing Code-Illustrated 



Table B.7.3.E CPVC, PVC, ABS PLASTIC PIPE - SCHEDULE 40 
WATER FLOW VELOCITY 


PIPE 
SIZE 


4FPS 


8FPS 


PIPE 
SIZE 


WSFU 
(tanks) 


WSFU 

(valves) 


FLOW 
GPM 


PD 

psi/lOOft 


WSFU 
(tanks) 


WSFU 
(valves) 


FLOW 
GPM 


PD 

psi/ 100ft 


1/2" 


4 




3.6 


5.2 


9 




7.3 


18.7 


1/2" 


3/4" 


7 




6.4 


3.7 


18 




12.9 


13.4 


3/4" 


I" 


14 




10.5 


2.8 


32 


4 


20.9 


10.1 


1" 


1-1/4" 


27 




18.2 


2.0 


71 


22 


36.4 


7.3 


1-1/4" 


1-1/2" 


40 


8 


24.9 


1.7 


124 


47 


49.7 


6.1 


1-1/2" 


2" 


89 


30 


41.1 


1.3 


286 


157 


82.2 


4.6 


2" 


2-1/2" 


168 


70 


58.5 


1.0 


460 


347 


117.1 


3.7 


2-1/2" 


3" 


328 


198 


90.6 


0.8 


820 


795 


181.2 


2.9 


3" 


4" 


675 


618 


156.5 


0.6 


1881 


1881 


313.1 


2.1 


4" 


5" 


1303 


1303 


246.4 


0.5 


3642 


3642 


492.8 


1.6 


5" 


6" 


2284 


2284 


356.2 


0.4 


7413 


7413 


712.4 


1.3 


6" 



Table B.7.3.F CPVC, PVC, ABS PLASTIC PIPE - SCHEDULE 80 
WATER FLOW VELOCITY 


PIPE 

SIZE 


4FPS 


8FPS 


PIPE 

SIZE 


WSFU 
(tanks) 


WSFU 
(valves) 


FLOW 
GPM 


PD 

psi/ 100ft 


WSFU 
(tanks) 


WSFU 
(valves) 


FLOW 
GPM 


PD 

psi/lOOft 


1/2" 


3 




2.7 


6.1 


7 




5.5 


22.1 


1/2" 


3/4" 


6 




5.1 


4.2 


14 




10.3 


15.3 


3/4" 


1" 


11 




8.6 


3.1 


25 




17.2 


11.3 


1" 


1-1/4" 


22 




15.4 


2.2 


55 


15 


30.8 


8.1 


1-1/4" 


1-1/2" 


33 


4 


21.3 


1.9 


95 


33 


42.7 


6.7 


1-1/2" 


2" 


70 


21 


35.8 


1.4 


233 


112 


71.7 


4.9 


2" 


2-1/2" 


132 


51 


51.4 


1.1 


389 


264 


102.7 


4.0 


2-1/2" 


3" 


277 


149 


80.3 


0.9 


698 


648 


160.7 


3.1 


3" 


4" 


585 


503 


140.4 


0.6 


1590 


1590 


280.7 


2.2 


4" 


5" 


1105 


1105 


222.6 


0.5 


3114 


3114 


445.3 


1.7 


5" 


6" 


1942 


1942 


319.2 


0.4 


5767 


5767 


638.3 


1.4 


6" 



Table B.7.3.G CPVC PLASTIC TUBING (Copper Tube Size) - SDR 11 
WATER FLOW VELOCITY 


TUBE 
SIZE 
(CTS) 


4FPS 


8FPS 


TUBE 
SIZE 
(CTS) 


WSFU 
(tanks) 


WSFU 
(valves) 


FLOW 
GPM 


PD 

psi/lOOft 


WSFU 
(tanks) 


WSFU 
(valves) 


FLOW 
GPM 


PD 

psi/lOOft 


1/2" 


2 




2.4 


6.6 


6 




4.8 


23.9 


1/2" 


3/4" 


6 




4.9 


4.4 


13 




9.8 


15.8 , 


3/4" 


1" 


10 




8.1 


3.3 


24 




16.2 


11.8 


1" 


1-1/4" 


16 




12.1 


2.6 


38 


7 


24.2 


9.3 


1-1/4" 


1-1/2" 


25 




16.9 


2.1 


62 


18 


33.7 


7.7 


1-1/2" 


2" 


50 


12 


28.9 


1.6 


164 


68 


57.8 


5.6 


2" 



2006 National Standard Plumbing Code-Illustrated 



389 



4. Mark on the schematic elevation, adjacent to ail fixture unit notations, the demand in gallons per minute 
corresponding to the various fixture unit loads in accordance with Table B.5.3. 

5. Mark, on the schematic elevation, for appropriate sections of the system, the demand in gallons per 
minute for outlets at which demand is considered continuous, such as outlets for watering gardens, irrigating 
lawns, air conditioning apparatus, refrigeration machines, and similar equipment using water at a relatively 
continuous rate during peak demand periods. Add the continuous demand to the demand for intermittently 
used fixtures, and show the total demand at those sections where both types of demand occur. (See Section 
B.5.4.) 

6. Size all individual fixture supply pipes to water outlets in accordance with the minimum sizes permitted 
by regulations. Minimum fixture supply pipe sizes for typical plumbing fixtures are given in Table B.5.2. 

7. Size all other parts of the water supply system in accordance with velocity limitations recognized as 
good engineering practice, and with velocity limitations recommended by pipe manufacturers for avoiding 
accelerated deterioration and failure of their products under various conditions of service. (Sizing tables 
based on such velocity limitations and showing permissible loads in terms of water supply fixture units for 
each size and kind of piping material have been provided and may be applied in this step.) (See Section B.6.) 

B.8 ILLUSTRATION OF SIMPLIFIED SIZING METHOD APPLICATION 

B.8.1 Example 

A three-story, nine-family multiple dwelling fronts on a public street and is supplied by direct street pressure 
from a public main in which the certified minimum pressure is 50 psi. The building has a full basement and 
three above-grade stories, each of which is 10' in height from floor to floor. The first floor is 2' above the 
curb level in front of the building. The public water main is located under the street: 5' out from and 4' 
below the curb. 

On each of the above-grade stories there are three dwelling units. Each dwelling unit has a sink and dish- 
washer, tank-type water closet, lavatory, and bathtub/shower combination. 

The basement contains two automatic clothes washing machines, two service sinks, and a restroom with a 
flush-tank water closet and lavatory. 

Two lawn faucets are installed, one on the front of the building and one in the rear. 

Hot water is to be supplied from a central storage-tank water heater. 

The water supply to the building will be metered at the water service entry point to the building. 

An isometric drawing of the water piping layout is shown in Figure B.8.1. 

B.8.2 Solution 

1 . All information necessary to develop the design must be obtained from appropriate sources. 

2. After the information is known, the isometric drawing (Figure B.8.1) is marked up with general water 
supply information, and the mains, risers, and branches are suitably identified. 

3. The water supply fixture unit loads are marked on the drawing next to each section of the system. 
These values are obtained from Tables B.5.2 and B.5.3. Many designers use parentheses marks for WSFU 
to distinguish them from gpm values. 

4. The maximum probable demand in gpm is marked on the drawing for each section next to the WSFU 
values. These values are obtained from Table B.5.4, using the columns for flush-tank systems. 

5. Where sections of the piping serve more than one hose bibb, each additional hose bibb adds a demand 
of 3 .0 WSFU to the piping. Wherever a section of piping serves a single hose bibb, it adds a demand of 2.5 
WSFU. 



390 2006 National Standard Plumbing Code-Illustrated 



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2006 National Standard Plumbing Code-Illustrated 




2006 National Standard Plumbing Code-Illustrated 



393 



Table B.8.2 
PRESSURE DROPS IN THE BASIC DESIGN CIRCUIT IN FIGURE B.8.2 



COLD WATER FRICTION PRESSURE DROP FROM MAIN TO "K" 


SECTION 


WSFU 

(1) 


FLOW 

(gpm) 


LENGTH 

(feet) 


PIPE 
SIZE 


VELOCITY 

(feet/second) 


PD 

(psi/100 ft) 


PRESSURE 
DROP (psi) 


MAIN -A 


66.0 


34.8 


50 


1-1/2" 


6.3 


4.0 


2.0 


A-B 


66.0 


34.8 


12 


1-1/2" 


6.3 


4.0 


0.5 


B-C 


57.6 


32.0 


8 


1-1/2" 


5.8 


3.6 


0.3 


C-D 


52.7 


30.1 J 


4 


1-1/4" 


7.7 


8.0 


0.3 


D-E 


44.4 


26.8 


8 


1-1/4" 


6.8 


6.0 


0.5 


E-F 


33.9 


22.0 


8 


1-1/4" 


5.6 


4.0 


0.3 


F-G 


15.4 


11.4 


10 


1" 


4.4 


3.2 


0.3 


G-H 


4.9 


10.0(6) 


4 


1"(4) 


3.9 


2.7 


0.1 


H-I 


2.4 


5.0(7) 


10 


3/4" (4) 


3.3 


2.7 


0.3 


I-J 


2.2 (2) 


5.0 (7) 


10 


3/4" (4) 


3.3 


2.7 


0.3 


J-K 


1.1 (2) 


2.5 (8) 


10 


1/2" (4) 


3.4 


4.3 


0.4 


Total Pipe Pressure Drop (psig) 


5.3 


Fitting Allowance (50% of pipe loss, psig) 


2.6 


Total Pressure Drop Due to Pipe Friction (psig) 


7.9 




HOT WATER FRICTION PRESSURE DROP FROM MAIN TO "K" 


SECTION 


WSFU 

(1) 


FLOW 

(gpm) 


LENGTH 

(feet) 


PIPE 
SIZE 


VELOCITY 

(feet/second) 


PD 

(psi/100 ft) 


PRESSURE 
DROP (psi) 


MAIN -A 


66.0 


34.8 


50 


1-1/2" 


6.3 


4.0 


2.0 


A-B 


66.0 


34.8 


12 


1-1/2" 


6.3 


4.0 


0.5 


B-HWH 


51.9 


29.8 


4 


1-1/4" 


7.6 


7.5 


0.3 


HWH-C 


51.9 


29.8 


4 


2" (5) 


3.1 


0.8 


0.0 


C-D 


47.4 


28.0 


10 


1-1/2" (5) 


5.0 


2.7 


0.3 


D-E 


39.1 


24.6 


8 


1-1/2" (5) 


4.4 


2.1 


0.2 


E-F 


30.1 


20.1 


8 


1-1/2" (5) 


3.6 


1.6 


0.1 


F-G 


13.5 


10.3 


10 


1"(5) 


4.0 


3.0 


0.3 


G-H 


4.5 


4.3 


4 


3/4" (4) 


2.9 


2.1 


0.1 


H-I 


4.5 


4.3 


10 


3/4" (4) 


2.9 


2.1 


0.2 


I-J 


4.0 (2) 


4.0 


10 


3/4" (4) 


2.7 


1.8 


0.2 


J-K 


2.0 (2) 


4.0(3) 


10 


3/4" (4) 


2.7 


1.8 


0.2 


Total Pipe Pressure Drop (psig) 


4.3 


Fitting Allowance (50% of pipe loss, psig) 


2.2 


Total Pressure Drop Due to Pipe Friction (psig) 


6.5 



NOTES FOR PRESSURE DROP CALCULATIONS 

(1) Water supply fixture units (WSFU) are for sections of piping serving 3 or more dwelling units except as noted by (2). 

(2) Water supply fixture units (WSFU) are for sections of piping serving fixtures in less than 3 dwelling units. 

(3) Water flow (gpm) for the dishwasher. 

(4) Velocity limited to 4 fps because of dishwashers and quick-closing sink faucets. 

(5) Velocity in copper tube with 140 deg F domestic hot water is limited to 5 fps using Chart B.9.8.3. 

(6) Allowance of 5 gpm for the hose bibb and two sinks at 2.5 gpm each. 

(7) Allowance for two sinks at 2.5 gpm each. 

(8) Allowance for one sink at 2.5 gpm. 

SUMMARY OF PRESSURE DROP CALCULATIONS 

Minimum pressure in water main = 50.0 psig. 

Water meter pressure drop = 3.0 psig 

Total cold water friction pressure drop from water main to "K" = 7.9 psig 

Total hot water friction pressure drop from water main to "K" = 6.5 psig 

Elevation pressure drop = (35 ft - 6 ft)(0.433) = 12.6 psig 

Cold water pressure available at "K" = 50-3-7.9 -12.6 = 26.5 psig 

Minimum required water pressure at "K" = 1 5 psig 

Therefore, the pipe sizing is satisfactory. 

If this calculation had shown that the pressure drop was excessive at "K", it would be necessary to examine the design for sections of the Basic 
Design Circuit that had the highest pressure drops and then increasse those segment pipe sizes. 



394 



2006 National Standard Plumbing Code-Illustrated 



6. All individual fixture supply pipes to water outlets are sized in Figure B.8.1 in accordance with the 
minimum sizes shown in Table B.5.2. 

7. All other parts of the system are sized in accordance with the velocity or pressure limitations estab- 
lished for this system as the basis of design. Piping is sized in accordance with the maximum probable 
demand for each section of the system. Sizing is done using Table B.7.3A through Table B.7.3H, and 
specifically the tables dealing with Copper Water Tube, Type K for sizing the water service pipe; and with 
Copper Water Tube, Type L, for sizing piping inside the building since these are the materials of choice as 
given in the general information on the drawing. 

B.8.3 Supplementary Check of Friction Loss in Main Lines and Risers 

A supplementary check of the total friction loss in the main lines and risers is made for the longest run of 
piping from the public water outlet to be sure that the sizes determined were adequate. This run has been 
shown in heavy lines with letters noted at various points. 

The sum of all friction losses due to flow through pipe, valves, and fittings is found to be 1 7.9 psi, whereas the 
amount of excess pressure available for such friction loss is 19.4 psi. Thus, the sizes determined on the basis 
of velocity limitations exclusively are proven adequate. Checking of friction loss in this case is performed 
following steps 8 through 15 of the Detailed Sizing Method for Building of Any Height presented in Section 
B.10. The calculations are shown on Figure B.8.2. 

B.8.4 Application to Systems in High Buildings 

This method of sizing, based upon the velocity limitations that should be observed in design of building water 
supply systems, has much broader application than just to systems in one-, two-, and three-story buildings 
where ample excess pressure is available at the source of supply. These velocity limitations should be ob- 
served in all building water supply systems. Thus, the sizes determined by this method are the minimum sizes 
recommended for use in any case. Where pipe friction is an additional factor to be considered in design, 
larger sizes may be required. 

B.9 LIMITATION OF FRICTION 

B.9.1 Basic Criterion 

The design of a building water supply system must be such that the highest water outlets will have available, 
during periods of peak demand, at least the minimum pressure required at such outlets for satisfactory water 
supply conditions at the fixture or equipment. 

B.9.2 Maximum Permissible Friction Loss 

The maximum allowable pressure loss due to friction in the water lines and risers to the highest water outlets 
is the amount of excess static pressure available above the minimum pressure required at such outlets when 
no-flow conditions exist. This may be calculated as the difference between the static pressure existing at the 
highest water outlets during no-flow conditions, and the minimum pressure required at such outlets for satis- 
factory supply conditions . 

Where water is supplied by direct pressure from a public main, to calculate the static pressure at the highest 
outlet, deduct from the certified minimum pressure available in the public main the amount of static pressure 
loss corresponding to the height at which the outlet is located above the public main (i.e., deduct 0.433 psi 
pressure for each foot of rise in elevation from the public main to the highest outlet). 



2006 National Standard Plumbing Code-Illustrated 395 



Where supplied under pressure from a gravity water supply tank located at an elevation above the highest 
water outlet, the static pressure at that outlet is calculated as being equal to 0.433 psi pressure for each foot 
of difference in elevation between the outlet and the water level in the tank. In this case, the minimum static 
pressure at the outlet should be determined as that corresponding to the level of the lowest water level at 
which the tank is intended to operate. 

B.9.3 Bask Design Circuit 

Of all the water outlets on a system, the one at which the least available pressure will prevail during periods 
of peak demand is the critical outlet that controls the design. Normally, it is the highest outlet that is supplied 
through the longest run of piping extending from the source of supply. 

This circuit is called the Basic Design Circuit (BDC) for sizing the main water lines and risers. 

In most systems, the BDC will be found to be the run of cold water supply piping extending from the source 
of supply to the domestic hot water vessel plus the run of hot water supply piping extending to the highest and 
most remote hot water outlet on the system. However, in systems supplied directly from the public main and 
having flushometer-valve water closets at the topmost floor, the BDC may be found to be the run of cold 
water supply piping extending from the public main to the highest and most remote flushometer valve on the 
system. 

B.9.4 Friction Loss in Equipment 

Where a water meter, water filter, water softener, fish trap or strainer, or instantaneous or tankless water 
heating coil is provided in the BDC, the friction loss corresponding to the maximum probable demand through 
such equipment must be determined and included in pressure loss calculations. Manufacturers' charts and 
data sheets on their products provide such information generally, and should be used as a guide in selecting 
the best type and size of equipment to use with consideration for the limit to which pressure loss due to 
friction may be permitted to occur in the BDC. The rated pressure loss through such equipment should be 
deducted from the friction loss limit to establish the amount of pressure that is available to be dissipated by 
friction in pipe, valves, and fittings of the BDC. 

B.9.5 Estimating Pressure Loss in Displacement Type Cold- Water Meters 

The American Water Works Association standard for cold-water meters of the displacement type is desig- 
nated AWWA C 700-64. It covers displacement meters known as nutating- or oscillating-piston or disc 
meters, which are practically positive in action. The standard establishes maximum capacity or delivery 
classification for each meter size as follows: 



5/8" 


20gpm 


3/4" 


30gpm 


1" 


50 gpm 


1-1/2" 


lOOgpm 


2" 


160 gpm 


3" 


3 00 gpm 



Also, the standard establishes the maximum pressure loss corresponding to these maximum capacities as 
follows: 

1 5 psi for the 5/8", 3/4" and 1 " meter sizes 

20 psi for the 1-1/2", 2", 3", 4" and 6" sizes. 



396 



2006 National Standard Plumbing Code-Illustrated 



B.9.6 Uniform Pipe Friction Loss 

To facilitate calculation of appropriate pipe sizes corresponding to the permissible friction loss in pipe, valves, 
and fittings, it is recommended that the BDC be designed in accordance with the principle of uniform pipe 
friction loss throughout its length. In this way, the friction limit for the piping run may be established in terms 
of pounds per square inch per 1 00 feet of piping length. The permissible uniform pipe friction loss in psi/1 00' is 
calculated by dividing the permissible friction loss in pipe, valves, and fittings by the total equivalent length of 
the basic design circuit, and multiplying by 1 00. 

B.9.7 Equivalent Length of Piping 

The total equivalent length of piping is its developed length plus the equivalent pipe length corresponding to the 
frictional resistance of all fittings and valves in the piping. When size of fittings are known, or has been 
established in accordance with sizes based upon appropriate limitation of velocity, corresponding equivalent 
lengths may be determined directly from available tables. Five such tables are included herein for various 
piping materials. See Tables B.9.7. A through B.9.7.E. 

As a general finding, it has been shown by experience that the equivalent length to be allowed for fittings and 
valves as a result of such calculations is approximately fifty percent of the developed length of the BDC in 
the case of copper water tube systems, and approximately seventy-five percent for standard threaded pipe 
systems. 

B.9.8 Determination of Flow Rates Corresponding to Uniform Pipe Friction Loss 

Flow rates corresponding to any given uniform pipe friction loss may be determined readily for each nominal 
size of the kind of pipe selected for the system. Pipe friction charts' are presented herewith for each of the 
standard piping materials used for water supply systems in buildings. The appropriate chart to apply in any 
given case depends upon the kind of piping to be used and the effect the water to be conveyed will produce 
within the piping after extended service. 

These charts are based on piping in average service. If piping is used in adverse service or in retrofit applica- 
tions, conservative practice suggests selecting lower flow rates for a given pipe, or larger pipe for a given 
required flow rate. 



For new work, with the range of materials now available, select a piping material that will not be affected by 
the water characteristics at the site. 



Table B.9.7.A 
EQUIVALENT LENGTH OF PIPE FOR FRICTION LOSS IN THREADED FITTINGS & VALVES 


Fitting or Valve 


Equivalent Feet of Pipe for Various Pipe Sizes 




1/2" 


3/4" 


1" 


1-1/4" 


1-1/2" 


2" 


2-1/2" 


3" 


4" 


5" 


6" 


45 deg Elbow 


0.8 


1.1 


1.4 


1.8 


2.2 


2.8 


3.3 


4.1 


5.4 


6.7 


8.1 


90 deg Elbow, std 


1.6 


2.1 


2.6 


3.5 


4.0 


5.2 


6.2 


7.7 


10.1 


12.6 


15.2 


Tee, run 


1.0 


1.4 


1.8 


2.3 


2.7 


3.5 


4.1 


5.1 


6.7 


8.4 


10.1 


Tee, Branch 


3.1 


4.1 


5.3 


6.9 


8.1 


10.3 


12.3 


15.3 


20.1 


25.2 


30.3 


Gate Valve 


0.4 


0.6 


0.7 


0.9 


1.1 


1.4 


1.7 


2.0 


2.7 


3.4 


4.0 


Globe Valve 


17.6 j 


23.3 


29.7 


39.1 


45.6 


58.6 


70.0 


86.9 


114 


143 


172 


Angle Valve 


7.8 


10.3 


13.1 


17.3 


20.1 


25.8 


30.9 


38.4 


50.3 


63.1 


75.8 


Butterfly Valve 












7.8 


9.3 


11.5 


15.1 


18.9 


22.7 


Swing Check Valve 


5.2 


6.9 


8.7 


11.5 


13.4 


17.2 


20.6 


25.5 


33.6 


42.1 


50.5 


NOTES FOR TABLE B.9.7.A " " 

1) Equivalent lengths for valves are based on the valves being wide open. 



2006 National Standard Plumbing Code-Illustrated 



397 



Table B.9.7.B 
EQUIVALENT LENGTH OF PIPE FOR FRICTION LOSS IN COPPER TUBE FITTINGS &VALVES 


Fitting or Valve 


Equivalent Feet of Pipe for Various Tube Sizes 




1/2" 


3/4" 


1" 


1-1/4" 


1-1/2" 


2" 


2-1/2" 


3" 


4" 


5" 


6" 


45 deg Elbow 


0.5 


0.5 


1.0 


1.0 


1.5 


2.0 


2.5 


3.5 


5.0 


6.0 


7.0 


90 deg Elbow, std 


1.0 


2.0 


2.5 


3.0 


4.0 


5.5 


7.0 


9.0 


12.5 


16.0 


19.0 


Tee, run 


0.0 


0.0 


0.0 


0.5 


0.5 


0.5 


0.5 


1.0 


1.0 


1.5 


2.0 


Tee, Branch 


2.0 


3.0 


4.5 


5.5 


7.0 


9.0 


12.0 


15.0 


21.0 


27.0 


34.0 


Gate Valve 


0.0 


0.0 


0.0 


0.0 


0.0 


0.5 


1.0 


1.5 


2.0 


3.0 


3.5 


Globe Valve 


17.6 


23.3 


29.7 


39.1 


45.6 


58.6 


70.0 


86.9 


114.0 


143.0 


172.0 


Angle Valve 


0.0 


0.0 


0.5 


0.5 


0.5 


0.5 


0.0 


0.0 


0.0 


0.0 


0.0 


Butterfly Valve 


7.8 


10.3 


13.1 


17.3 


20.1 


25.8 


30.9 


38.4 


50.3 


63.1 


75.8 


Swing Check Valve 












7.5 


10.0 


15.5 


16.0 


11.5 


13.5 


Fitting or Valve 


2.0 


3.0 


4.5 


5.5 


6.5 


9.0 


11.5 


14.5 


18.5 


23.5 


26.5 


NOTES FOR TABLE B.9.7.B 

1 ) Equivalent lengths for valves are based on the valves being wide open. 

2) Data based in part on the 2004 Copper Tube Handbook by the Copper Development Association. 



Table B.9.7.C 
EQUIVALENT LENGTH OF PIPE FOR FRICTION LOSS IN SCHEDULE 40 CPVC FITTINGS 



Fitting 



Equivalent Feet of Pipe for Various Pipe Sizes 



1/2" 



3/4" 



I" 



1-1/4" 



1-1/2" 



2-1/2" 



3" 



45 deg Elbow 



0.8 



1.1 



1.4 



2.1 



2.7 



3.3 



4.1 



5.3 



6.7 



8.0 



90 deg Elbow 



1.5 



2.0 



2.6 



3.4 



4.0 



5.1 



6.1 



7.6 



10.0 



12.5 



15.1 



Tee, Run 



1.0 



1.4 



1.7 



2.3 



2.7 



3.4 



4.1 



5.1 



6.7 



8.4 



10.1 



Tee, Branch 



3.0 



4.1 



5.2 



6.8 



8.0 



10.2 



12.2 



15.2 



20.0 



25. 



30.2 



Table B.9.7.D 
EQUIVALENT LENGTH OF PIPE FOR FRICTION LOSS IN SCHEDULE 80 CPVC FITTINGS 


Fitting 


Equivalent Feet of Pipe for Various Pi 


pe Sizes 




1/2" 


3/4" 


1" 


1-1/4" 


1-1/2" . 


2" 


2-1/2" 


3" 


4" 


5" 


6" 


45 deg Elbow 


0.7 


1.0 


1.2 


1.7 


2.0 


2.6 


3.1 


3.8 


5.0 


6.4 


7.6 


90 deg Elbow 


1.3 


1.8 


2.3 


3.1 


3.7 


4.8 


5.7 


7.2 


9.5 


11.9 


14.3 


Tee, Run 


0.9 


1.2 


1.6 


2.1 


2.5 


3.2 


3.8 


4.8 


6.3 


7.9 


9.5 


Tee, Branch 


2.6 


3.6 


4.7 


6.3 


7.4 


9.6 


11.5 


14.3 


18.9 


23.8 


28.5 



Table B.9.7.E 

EQUIVALENT LENGTH OF PIPE 

FOR FRICTION LOSS IN CPVC SDR 11 CTS TUBING FITTINGS 


Fitting 


Equivalent Feet of Pipe for Various Pipe Sizes 




1/2" CTS 


3/4" CTS 


1 " CTS 


1-1/4" CTS 


1-1/2" CTS 


2" CTS 


45 deg Elbow 


0.8 


1.1 


1.4 


1.8 


2.2 


2.8 


90 deg Elbow 


1.6 


2.1 


2.6 


3.5 


4.0 


5.2 


Tee, Run 


1.0 


1.4 


1.8 


2.3 


2.7 


3.5 


Tec, Branch 


3.1 


4.1 


5.3 


6.9 


8.1 


10.3 



398 



2006 National Standard Plumbing Code-Illustrated 



B.10 DETAILED SIZING METHOD FOR SYSTEMS IN 
BUILDINGS OF ANY HEIGHT 

For sizing water supply systems in buildings of any height, a detailed method may be applied in the design of 
modern buildings. The procedure consists of sixteen steps, as follows: 

1. Obtain all information necessary for sizing the system. Such information shall be obtained from responsible 
parties and appropriate local authorities recognized as sources of the necessary information. (See Section B.2.) 

2. Provide a schematic elevation of the complete water supply system. Show all piping connections in proper 
sequence and all fixture supplies. Identify all fixtures and risers by means of appropriate letters, numbers, or 
combinations thereof. Identify all piping conveying water at a temperature above 150°F, and all branch piping to 
such water outlets as solenoid valves, pneumatic valves, or quick-closing valves or faucets. Provide on the sche- 
matic elevation all the general information obtained per step 1 . (See Section B.2.9.) 

3. Mark on the schematic elevation, for each section of the complete system, the hot and cold water loads 
served in terms of water supply fixture units in accordance with Table B.5.2. 

4. Mark on the schematic elevation, adjacent to all fixture unit notations, the probable maximum demand in 
gallons per minute corresponding to the various fixture unit loads in accordance with Table B.5.4. 

5. Mark on the schematic elevation, for appropriate sections of the system, the demand in gallons per minute 
for outlets at which demand is considered continuous, such as outlets for watering gardens, irrigating lawns, air- 
conditioning apparatus, refrigeration machines, and similar equipment. Add the continuous demand to the demand 
for intermittently used fixtures, and show the total demand at those sections where both types of demand occur 
(See Section B.5.4.) 

6. Size all individual fixture supply pipes to water outlets in accordance with the minimum sizes permitted by 
regulations. Minimum fixture supply pipe sizes for typical plumbing are given in Table B.5 .2. 

7. Size all other parts of the water supply system in accordance with velocity limitations recognized as good 
engineering practice, and with velocity limitations recommended by pipe manufacturers for avoiding accelerated 
deterioration and failure of their products under various conditions of service. Sizing tables based on such velocity 
limitations and showing permissible loads in terms of water supply fixture units for each size and kind of piping 
material have been provided and may be applied as a convenient and simplified method of sizing in this step. (See 
Section B.6) 

Note: These sizes are tentative until verified in Steps 12, 13, 14, 15. 

8. Assuming conditions of no-flow in the system, calculate the amount of pressure available at the topmost 
fixture in excess of the minimum pressure required at such fixtures for satisfactory supply conditions. This excess 
pressure is the limit for friction losses for peak demand in the system (1' of water column = 433 psi pressure) 
(See Section B.9.2.) 

9. Determine which piping circuit of the system is the basic one for which pipe sizes in main lines and riser 
should be designed in accordance with friction loss limits. This circuit is the most extreme run of piping through 
which water flows from the public main, or other source of supply, to the highest and most distant water outlet. 
This basic design circuit (BDC) should be specifically identified on the schematic elevation of the system (See 
Section B.9.3.) 

10. Mark on the schematic elevation the pressure loss due to friction corresponding to the maximum probable 
demand through any water meter, water softener, or instantaneous or tankless water heating coil that may be 
provided in the BDC. (See Sections B.9.4 and B.9.5.) 

11. Calculate the amount of pressure remaining and available for dissipation as friction loss during peak demand 
through pipe, valves, and fittings in the BDC. Deduct from the excess static pressure available at the topmost 
fixtures (determined in step 8), the friction losses for any water meters, softeners, and water heating coils provided 
in the BDC determined in step 10. (See Section B.9.4.) 

12. Calculate the total equivalent length of the BDC. Pipe sizes established on the basis of velocity limitation in 
step 7 for main lines and risers must be considered just tentative at this stage, but may be deemed appropriate for 
determining corresponding equivalent lengths of fittings and valves in this step. (See Section B.9.7.) 



2006 National Standard Plumbing Code-Illustrated 300 



GALVANIZED STEEL 
ASTM A53 



1000 
800 




.2 25 .3 .4 .5.6 .8 1 ' 5 2 " 3 4 5 6 8 10 1S 20 ^30 40 5060 80100 



PRESSURE DROP (psi/100 1 ) 

FLOWVS. PRESSURE DROP 
CHART B.9.8.1 



400 



2006 National Standard Plumbing Code-Illustrated 



TYPEK 
COPPER TUBE 



&t <$? <b\t 



9^ $& $St 



1000 
800 




1 '- 5 2 2 - 5 3 4 5 6 8 10 ,5 20 25 30 40 5060 80100 



PRESSURE DROP (psi/100') 

FLOWVS. PRESSURE DROP 
CHART B.9.8.2 



2006 National Standard Plumbing Code-Illustrated 



401 



TYPEL 
COPPER TUBE 



tisr <W ®t 




20 25 30 40 5060 80100 



PRESSURE DROP (psi/100') 

FLOWVS. PRESSURE DROP 
CHART B.9.8.3 



402 



2006 National Standard Plumbing Code-Illustrated 



TYPEM 
COPPER TUBE 



$& <$f &f 



g) J£> Jd J$ 




5 6 8 10 ,s 20 2S 30 40 5060 80100 



PRESSURE DROP (psi/100') 

FLOWVS. PRESSURE DROP 
CHART B.9.8.4 



2006 National Standard Plumbing Code-Illustrated 



403 



&r 



CPVC / PVC / ABS 
SCHEDULE 40 PIPE 




.3 .4 .5.6 .8 1 



2 M 3 4 5 6 8 10 ,s 20 ^O 40 5060 80100 



PRESSURE DROP (psi/100') 

FLOWVS. PRESSURE DROP 
CHART B.9.8.5 



404 



2006 National Standard Plumbing Code-Illustrated 



CPVC / PVC / ABS 
SCHEDULE 80 PIPE 




■ 1 15 .2 25 .3 .4 .5.6 .8 



2 25 3 4 5 6 8 10 



20 25 30 40 5060 80100 



PRESSURE DROP (psi/100') 

FLOWVS. PRESSURE DROP 
CHART B.9.8.6 



2006 National Standard Plumbing Code-Illustrated 



405 



CPVC TUBING 
COPPER TUBE SIZE - SDR 1 1 ) 

! \ i 




.3 .4 .5.6 .8 1 1 - 5 2 2 - 5 3 4 5 6 8 10 15 20 25 30 40 5060 80100 

PRESSURE DROP (psi/100') 

FLOWVS. PRESSURE DROP 
CHART B.9.8.7 



406 



2006 National Standard Plumbing Code-Illustrated 



13. Calculate the permissible uniform pressure loss for friction in piping of the BDC. The amount of pressure 
available in the circuit for dissipation as friction loss due to pipe, fittings, and valves (determined in step 1 1), is 
divided by the total equivalent length of the circuit (determined in step 12). This establishes the pipe friction limit 
for the circuit in terms of pressure loss in psi per foot of total equivalent pipe length. Multiply this value by 1 00 in 
order to express the pipe friction limit in terms of psi per 100 feet of length. (See Section B.9.6.) 

14. Set up a sizing table showing the rates of flow for various sizes of the kind of piping to be used, correspond- 
ing to the permissible uniform pressure loss for pipe friction calculated for the BDC (determined in step 13). Such 
rates may be determined from a pipe friction chart appropriate for the piping to be used and for the effects upon 
the piping of the quality of the water to be conveyed thereby for extended service. (See Sections B.9.8 and B.2.3.) 

15. Check the sizes of all parts of the BDC, and all other main lines and risers which supply water upward to 
the highest water outlets on the system, in accordance with the sizing table set up in step 14. Where sizes deter- 
mined in this step are larger than those previously established in step 7 (based on velocity limitation), the increased 
size is applicable for limitation of friction. 

16. Due consideration must be given to the action of the water on the interior of the piping, and proper allow- 
ance must be made where necessary as a design consideration, such as, where the kind of piping selected and the 
characteristics of the water conveyed are such that an appreciable buildup of corrosion products or hard-water 
scale may be anticipated to cause a significant reduction in bore of the piping system and inadequate capacity for 
satisfactory supply conditions during the normal service life of the system. A reasonable allowance in such cases is 
to select at least one standard pipe size larger than the sizes determined in the preceding steps. Where the water 
supply is treated in such manner as to avoid buildup of corrosion products or hard- water scale, no allowance need 
be made in sizing piping conveying such treated water. (See Sections B.2.3 and B.9.8.) 

B.ll ILLUSTRATION OF DETAILED SIZING METHOD APPLICATION 

B. 11.1 Example 

A seven-story building is supplied by direct street pressure from a public water main in which the minimum 
available pressure is 60 psi. The highest fixture supplied is 64'-8" above the public main, and requires 12 psi 
flow pressure at the fixture for satisfactory supply conditions. 

The water supply is to be metered by a meter through which flow at the maximum probable demand rate will 
produce a pressure drop of 5.6 psi. Copper tubing, Type L, is to be used for the entire system. Quality of the 
water supply is known to be noncorrosive to copper tubing in the water district, and is recognized as being 
non-scaling in characteristic. 

The entire system has been initially sized in accordance with the simplified method based solely on velocity 
limitations. Applying these sizes, the total equivalent length of piping from the public main to the highest and 
most remote fixture outlet has been calculated to be 600'. 

B.l 1.2 Solution 

Steps 1-7. The first seven steps of the details sizing method have already been performed. These steps 
constitute the simplified sizing method based solely on velocity limitations established as the design basis. All 
that remains is to perform steps 8 through 1 5 of the detailed sizing method which relate to sizing in accor- 
dance with the frictional limitation which must be observed for this particular system, and with allowances 
which may be necessary in view of the water characteristics. 

Step 8. Assuming conditions of no-flow in the system, the amount of excess pressure available at the 
topmost fixture in excess of the minimum required at the fixture for satisfactory supply conditions is deter- 
mined as follows: 



2006 National Standard Plumbing Code-Illustrated 407 



Excess pressure available = 60 psi - 12 psi - (64.67 x 0.4333 psi/ft) = 20 psi 

Step 9. The BDC should be specifically identified on the schematic elevation provided as per step 2. 

Step 10. The pressure loss through the water meter selected for this system for flow at maximum probable 
demand is given in the example as being 5.6 psi. No other items of equipment through which significant 
friction losses may occur have been noted in the example. 

Step 1 1 . The amount of pressure remaining for dissipation as friction loss during peak demand through 
pipes, valves, and fittings in the basic design circuit is determined as follows: 
Pressure available for friction in piping = 20 psi - 5.6 psi = 14.4 psi 

Step 12. The total equivalent length of the basic design circuit has been given in the example as being 600 
feet, based on the sizes determined in accordance with velocity limitations as per step 7. 

Step 13. The permissible uniform pressure loss for friction in piping of the basic design circuit is deter- 
mined as follows: 

Permissible uniform pipe friction loss = 14.4 psi x (1 00 ft/600 ft) 
= 2.4 psi per 100 ft pipe length 

Step 14. A sizing table showing the rates of flow through various sizes of copper tubing corresponding to a 
pipe friction loss rate of 2.4 psi per 100 feet of pipe length is given in Table B.l 1 .2. These flow rates were 
determined from the chart applicable to such pipe with a "fairly smooth" surface condition after extended 
service conveying water having the effect stated in the example. 

Step 15. All parts of the BDC should be selected in accordance with the flow rates shown in the table 
established in step 14. Usually, all other parts of the system are sized using the same pressure drop limitation. 



Table JB.11.2 

TYPE L COPPER TUBING, FOR "FAIRLY SMOOTH" CONDITION 

Nominal Pipe Flow Rates Corresponding to Friction 

Size Lossof2.4psi/100' 

(■"> (gpm) 

1/2 1.4 

3/4 3.9 

1 7.5 
1-1/4 14.0 
1-1/2 21.0 

2 47.0 
2-1/2 78.0 

3 130.0 

4 270.0 



B.l 2 MANIFOLD TYPE PARALLEL WATER DISTRIBUTION SYSTEMS 

B. 12.1 Manifolds 

The total water supply demand for the dwelling shall be determined in accordance with Section 10. 14 and 
Appendix B.5. Manifolds shall be sized according to Table B.12.1 based on the total supply demand. 



'*"" 2006 National Standard Plumbing Code-Illustrated 





Table 


B.12.1 












MANIFOLD SIZING 1 








Nominal Size ID 






Maximum 


GPM Available @ 


Velocity 




Inches 


i 


@4 fps 




@8fps 




@ 10 fps 


1/2 

3/4 




2 
6 




5 
11 




6 
14 


1 
1-1/4 




10 
15 




20 

31 




25 
38 


1-1/2 




22 




44 




55 



Refer to Section 10.14 for maximum velocity permitted. 



B.12.2 Distribution Lines 



a. The water pressure available for distribution pipe friction shall be determined from the minimum supply 
pressure available at the source, the developed length and size of the water service, the pressure drop through 
the water meter (if provided), the pressure drop through the manifold, the pressure drop through any other 
equipment or appurtenances in the system, the elevation of each distribution line, and the minimum pressure 
required at each fixture. 

b. The water flow required at each fixture shall be in accordance with Section 10. 14.2a for both hot and 
cold water. Distribution line sizes shall be in accordance with the system manufacturer's line sizing proce- 
dure. 

c. The system manufacturer shall provide sizing data for the individual runs of tubing to each fixture based 
on the water pressure available for pipe friction and static elevation, the GPM required at each fixture, the 
tubing material, the tube size, and its maximum allowable length from the manifold to the fixture. Tube sizes 
forparallel water distribution systems include 3/8" nominal, 1/2" nominal, and 3/4" nominal. 



2006 National Standard Plumbing Code-Illustrated 4QO, 



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410 2006 National Standard Plumbing Code-Illustrated 







Lppendix C 



Conversions: 
Customary Units to Metric 



Square Measure Conversions from 

Square Inches to 

Approximate Square Centimeters and 

Square Feet to Approximate Square Meters 



Square 


Square 


Square 


Square 






Inches 


Centimeters 


Feet 


Meters 






1 


6.5 


1 


.0925 




2 


13.0 


2 


.1850 






3 


19.5 


3 


.2775 






4 


26.0 


4 


.3700 






5 


32.5 


5 


.4650 






6 


39.0 


6 


.5550 






7 


45.5 


7 


.6475 






8 


52.0 


8 


.7400 






9 
10 

25 


58.5 

65.0 

162.5 


9 
10 

25 


.8325 
.9250 
2.315 


Temperature 
Degrees 


Conversions from 
Fahrenheit to 


50 


325.0 


50 


4.65 


Approximat 


e Degrees Celsius 


100 


650.0 


100 


9.25 






l \j\j 


Fahrenheit (°F) 


Celsius (°C) 




32° 


0° 










40° 


4° 










50° 
60° 
70° 


10° 
15° 

21° 


















80° 


26° 










90° 


32° 










100° 


38° 










120° 


49° 










140° 


60° 










160° 


71° 










180° 


82° 










200° 


93° 










212° 


100° 







2006 National Standard Plumbing Code-Illustrated 



411 



Liquid Volume Time Conversions 
(Flow-Rate Conversions) 
From Gallons Per Minute 

to Approximate Litres Per Minute 



;pm 


Litres/Minute 


1 


3.75 


2 


6.50 


3 


11.25 


4 


15.00 


5 


18.75 


6 


22.50 


7 


26.25 


8 


30.00 


9 


33.75 





37.50 



Liquid Volume Conversions from 

Liquid Ounces and 

U.S. Gallons to Litres 



Ounces Litres 



1 


.0296 


2 


.0591 


3 


.0887 


4 


.1183 


5 


.1479 


6 


.1774 


7 


.2070 


8 


.2366 


9 


.2662 


10 


.2957 


16(1 pt.) 


.4732 


20 


.5915 


30 


.8872 


32 (1 qt.) 


.9464 



Gallons 



Litres 



1/4 


.9464 


1/2 


1.893 


3/4 


2.839 


1 


3.785 


2 


7.571 


3 


11.36 


4 


15.14 


5 


18.93 


6 


22.71 


7 


26.50 


8 


30.28 


9 


34.07 


10 


37.85 


20 


75.71 


30 


113.6 


40 


151.4 


50 


189.3 


100 


378.5 



Length/Time Conversions from 

Feet Per Second to 
Approximate Meters Per Second 



Feet Per 


Meters Per 


Second 


Second 


1 


.3050 


2 


.610 


3 


.915 


4 


1.220 


5 


1.525 


6 


1.830 


7 


2.135 


8 


2.440 


9 


2.754 


10 


3.05 



Mass Conversions from 
Ounces and Pounds to Kilograms 



Ounces 



Kilograms 



1 


.028 


2 


.057 


3 


.085 


4 


.113 


5 


.142 


6 


.170 


7 


.198 


8 


.227 


9 


.255 


10 


.283 


11 


.312 


12 


.340 


13 


.369 


14 


.397 


15 


.425 


16 (lib.) 


.454 



Pounds Kilograms 



1 


.454 


2 


.907 


3 


1.361 


4 


1.814 


5 


2.268 


6 


2.722 


7 


3.175 


8 


3.629 


9 


4.082 


10 


4.536 


25 


11.34 


50 


22.68 


75 


34.02 


00 


45.36 



412 



2006 National Standard Plumbing Code-Illustrated 






Determining the Minimum Number of 
Required Plumbing Fixtures 



The determination of the minimum number of required plumbing fixtures is a complex issue as many buildings are 
unique as such the Authority Having Jurisdiction is called upon to use good judgement in applying this procedure. 



1. DETERMINE THE SERVICE POPULATION 

The population for the building or facility should be given on the plans. In the event the population of the building 
or service area is not given on the plans, three approaches may be utilized in determining the population to be 
served by the restroom facility. 

( a.) Actual: In some instances the actual population, male and female, of the building service area may be 
known and this value may be used in the calculations. 

(b) Engineering Estimate: The population of many buildings, especially those owner-occupied, may be 
determined on the basis of population densities. Typically, office building floor areas range from 200 to 400 square 
feet per person. In the absence of other data, the gender ratio should be 60/60 which allows for a variance. 

(c) Legal Limit: Many building codes establish a legal occupancy limit based on the means of egress. Where 
the occupant load is based on the egress requirements of a building, the number of occupants for plumbing pur- 
poses shall be permitted to be reduced to two-thirds of that required for fire or life safety purposes. 

2. MINIMUM NUMBER OF REQUIRED PLUMBING FIXTURES 

The minimum number of required plumbing fixtures shall be determined based on building classification, user group 
and population as given in Table 7.21.1. The building classifications and user groups are consistent with nationally 
recognized building codes. 

EXAMPLE A 

Building classification, use group, total population must be known. 



Building classification: 
Use Group: 
Floor area: 
Population 



Assembly 

A-3, auditorium without permanent seating 

20,000 net square feet, 1 story 

2,857 based on egress per the Building Code at 7 sq ft per person 



2006 National Standard Plumbing Code-Illustrated 



413 



1. Determine the Plumbing Population 

Since the given population is based on egress requirements, the population for plumbing purposes can be 2/3 of 
that value (Section 7.21.2.b). The ratio of male and female occupants can be assumed to be 50% each (Section 
7.21.2.C). 

Population for plumbing purposes = 2857x2/3 = 1 905 
Male population = 1905 x 50% = 953 
Female population = 1905 x 50% = 953 

2. Determine the Minimum Required Number of Plumbing Fixtures 

The minimum required number of plumbing fixtures is determined from Table 7.21.1 under 
No. 1 Assembly, Use Group A-3 

The number of males and females are greater than the numerical groups listed in Table 7.21.1. To determine the 
total number of fixtures required, calculate the number of fixtures required by the listed numerical groups and then 
determine how many additional groups of 300 there are over the first 300. 

Male Water Closets 



first 50 men (1-50) = 1 water closet 

next 100 men (51-150) = add 1 water closet 

next 150 men (151-300) = add water closet 

add 1 for each additional group of 300 over 300 (or parts thereof) 

The listed numerical groups account for the first 300 males 

The number of additional groups of 300 = (953 - 300) divided by 300 per group = 2.18 = 3 groups 

The total number of male water closets = 1 (first 50) 

= 1 (next 100) 
= (next 150) 
= 3 (3 additional groups of 300 @ 1 each) 

Minimum number of water closets for males = 5 

Section 7. 21. 5. a permits urinals to be substituted for up to 50% of the required water closets. 

The male toilet room could contain 3 water closets and 2 urinals. 

Female Water Closets 



first 50 females (1-50) = 1 water closet 

next 100 females (51-150) = add 1 water closet 

next 150 females (151-300) = add water closet 

add 2 for each additional group of 300 over 300 (or parts thereof) 

The listed numerical groups account for the first 300 females. 

The number of additional groups of 300 = (953 - 300) divided by 300 per group = 2. 18 = 3 groups 

The total number of female water closets = 1 (first 50) 

= 1 (next 100) 
= (next 150) 
= 6 (3 additional groups of 300 @ 2 each) 



414 



2006 National. Standard Plumbing Code-Illustrated 



Minimum number of water closets for females = 8 
Male Lavatories 



first 50 males (1-50) = 1 lavatory 

next 100 males (5 1-150) = add lavatories 

next 150 males (151-300) = add lavatories 

add 1 for each additional group of 300 over 300 (or parts thereof) 

The total number of male lavatories = 1 (first 50 

= (next 100) 



= next 150) 

= 3 (3 additional groups of 300 @ 1 each) 



Minimum number of lavatories for males = 4 
Female Lavatories 



first 50 females (1-50) = 1 lavatory 

next 100 females (51-150) = add 1 lavatory 

next 150 females (151-300) = add lavatories 

add 2 for each additional group of 300 over 300 (or parts thereof) 

The total number of female lavatories = 1 (first 50 

= 1 (next 100) 



= next 150) 

= 6 (3 additional groups of 300 @ 2 each) 



Minimum number of lavatories for females = 8 
Drinking Water Facilities 



Table 7.21.1 requires 1 per 1000 people (or parts thereof) 

Number of drinking water facilities = 1905 divided by 1000 per group = 1.905 = 2 groups 



Service Sinks 



Table 7.21.1 requires a minimum of 1 per floor. 



2006 National Standard Plumbing Code-Illustrated 41c 



EXAMPLE B 

Building classification, use group, total population must be known. 

Building classification: Business 

Use Group: B, office building 

Floor area: 48,300 net square feet, 1 story 

Population 386 based on expected occupancy 

1. Determine the Plumbing Population 

Population for plumbing purposes = 386 
Male population = 386 x 50% = 193 
Female population = 386 x 50% = 193 

2. Determine the Minimum Required Number of Plumbing Fixtures 

The minimum required number of plumbing fixtures is determined from Table 7.21 . 1 under 
No. 2 Business, Use Group B 

The number of males and females are greater than the numerical groups listed in Table 7.21.1. To determine the 
total number of fixtures required, calculate the number of fixtures required by the listed numerical groups and then 
determine how many additional groups of 60 there are over the first 75. 

Male Water Closets 

first 15 men (1-15) = 1 water closet 

next 25 men (16-40) = add 1 water closet 

next 35 men (40-75) = add 1 water closet 

add 1 for each additional group of 60 over 75 (or parts thereof) 

The listed numerical groups account for the first 75 males 

The number of additional groups of 60 = (193 - 75) divided by 60 per group = 1.97 = 2 groups 

The total number of male water closets = 1 (first 15) 

= 1 (next 25) 
= 1 (next 35) 
= 2 (2 additional groups of 60 @ 1 each) 

Minimum number of water closets for males = 5 

Section 7.21 .5a permits urinals to be substituted for up to 50% of the required water closets. 

The male toilet room could contain 3 water closets and 2 urinals. 

Female Water Closets 

first 15 females (1-15) = 1 water closet 

next 25 females (16-40) = add 1 water closet 

next 35 females (40-75) = add 1 water closet 

add 2 for each additional group of 60 over 75 (or parts thereof) 

The listed numerical groups account for the first 75 females. 



416 2006 National Standard Plumbing Code-Illustrated 



The number of additional groups of 60 = (193 - 75) divided by 60 per group = 1.97 = 2 groups 

The total number of female water closets = 1 (first 15) 

= 1 (next 25) 
= 1 (next 35) 
= 4 (2 additional groups of 60 @ 2 each) 

Minimum number of water closets for females = 7 

Male Lavatories 

first 15 males (1-15) = 1 lavatory 

next 25 males (16-40) = add lavatories 

next 35 males (40-75) = add 1 lavatory 

add 1 for each additional group of 60 over 75 (or parts thereof) 

The total number of male lavatories = 1 (first 1 5 

= (next 25) 
= 1 (next 35) 
= 2 (2 additional groups of 60 @ 1 each) 

Minimum number of lavatories for males = 4 

Female Lavatories 

first 15 females (1-15) = 1 lavatory 

next 25 females (16-40) = add 2 lavatories 

next 35 females (41-75) = add 1 lavatories 

add 2 for each additional group of 60 over 75 (or parts thereof) 

The total number of female lavatories = 1 (first 15) 

= 2 (next 25) 
= 1 (next 35) 
= 4 (2 additional groups of 60 @ 2 each) 

Minimum number of lavatories for females = 8 
Drinking WaterFacilities 



Table 7.21.1 requires 1 per 1000 people (or parts thereof) 

Number of drinking water facilities = 386 divided by 1000 per group = 0.39 = 1 group 

Service Sinks 

Table 7.21 . 1 requires a minimum of 1 per floor. 



2006 National Standard Plumbing Code-Illustrated 



AY! 



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418 2006 National Standard Plumbing Code-Illustrated 



^^^^^^^^^^^g^j^ ^^^^^^^H^^ ^^^^ ^^^^^ g^ 






^pccim ucsi§n 
Plumbing Systems 



E.l GENERAL REQUIREMENTS 

E.l.l Special design plumbing systems shall include all systems that vary in detail from the requirements of 
this Code. 

E.1.2 The provisions of this Appendix shall control the design, installation, and inspection of special design 
plumbing systems. 

E.1.3 Special design plumbing systems shall conform to the Basic Principles of this Code. 

E.1.4 Special design plumbing systems shall be designed by a registered design professional who is licensed to 
practice in the particular jurisdiction. 

E.2 PLANS, SPECIFICATIONS, AND COMPUTATIONS 

E.2.1 Plans, specifications, computations, and other related data for special design plumbing systems, 
prepared by the registered design professional, shall be submitted to the Authority Having Jurisdiction for 
review and approval prior to installation. 

£.2.2 The design plans shall indicate that the plumbing system (or portions thereof) is a special design 
system. 

E.3 INSTALLATION OF SPECIAL DESIGN PLUMBING SYSTEMS 

E.3.1 Special design plumbing systems shall be installed according to established, tested and approved criteria, 
including manufacturer's instructions. 

E.3.2 The installation shall comply with Chapter 2 - General Regulations and other applicable requirements 
of this Code. 



2006 National Standard Plumbing Code-Illustrated 419 



E.4 CERTIFICATION OF COMPLIANCE 

E.4.1 Inspections shall be made by the Authority Having Jurisdiction to ensure conformance with data 
submitted for approval and the applicable requirements of this Code. 

E.4.2 The complete installation and performance of the special design plumbing system shall be certified 
by the registered design professional as complying with the requirements of the special design. 

E.5 VACUUM DRAINAGE SYSTEMS 
E.5.1 General Requirement 

E.5.1. 1 System Design 

Vacuum drainage systems shall be designed in accordance with manufacturer's recommendations. The 
system layout, including piping layout, tank assemblies, vacuum pump assembly and other components/ 
designs necessary for proper function of the system shall be per manufacturer's recommendations. Plans, 
specifications and other data for such systems shall be submitted to the Authority Having Jurisdiction for 
review and approval prior to installation. 

E.5.1.2 Fixtures 

Gravity type fixtures used in vacuum drainage systems shall comply with Chapter 7 of this Code. 

E.5.1. 3 Drainage Fixture Units 

Fixture units for gravity drainage systems that discharge into or receive discharge from vacuum drainage 
systems shall be based upon values in Chapter 1 1 of this Code. 

E.5.1.4 Water Supply Fixture Units 

Water supply fixture units shall be based upon values in Chapter 10 of this Code with the addition that the 
fixture unit of a vacuum type water closet shall be one inch. 

E.5.1 .5 Traps and Cleanouts 

Gravity type fixtures shall be provided with traps and cleanouts per Chapter 5 of this Code. 

E.5.1.6 Materials 

Vacuum drainage pipe, fittings and valve materials shall be as recommended by the vacuum drainage 
system manufacturer and as permitted by this Code. 

E.5.2 Tests and Demonstrations 

After completion of the entire system installation, the system shall be subjected to a vacuum test of 19 inches 
of mercury and shall be operated to function as required by the Authority Having Jurisdiction and the manu- 
facturer. Recorded proof of all tests shall be submitted to the Authority Having Jurisdiction. 



42U 2006 National Standard Plumbing Code-Illustrated 



E.5.3 Written Instructions 

Written instructions for the operation, maintenance, safety and emergency procedures shall be provided to the 
Building Owner as verified by the Authority Having Jurisdiction. 

E.6 ONE-PIPE SANITARY DRAINAGE SYSTEMS EMPLOYING AERATOR AND 
DE AERATOR STACK FITTINGS 

E.6.1 Compliance 

a. One-pipe sanitary drainage systems employing aerator and deaerator stack fittings shall be permitted to be 
installed in accordance with (1) the fitting manufacturer's current piping design manual and technical bulletins, 
and (2) the applicable requirements of this Code. 

b. The requirements of this Code shall supercede the fitting manufacturer's piping design manual with regard 
to acceptable piping materials, drainage fixture unit (DFU) values, and minimum drainage pipe sizes. 

c. Complete detailed layout drawings shall be prepared prior to the installation of such a sanitary drainage 
system. 

E.6.2 Piping Materials 

Piping materials for drainage stacks and branches shall be in accordance with Section 3.5 of this Code. Piping 
materials for vents shall be in accordance with Section 3.6 of this Code. 

E.6.3 Drainage Fixture Unit (DFU) Values 

Drainage fixture unit values for bathroom groups and individual fixtures shall be in accordance with Table 1 1 .4. 1 
of this Code. 

E.6.4 Drainage Pipe Sizing 

Piping in such a sanitary drainage system shall be sized according to the fitting manufacturer's current piping 
design manual. 

EXCEPTION: Drainage pipe sizes shall not be less than those required by Section 1 1.5 of this Code. 

E.6.5 Arrangement of Piping 

Piping shall be arranged as illustrated in the fitting manufacturer's current design manual. 

E.7 SINGLE STACK VENT SYSTEMS 

E.7.1 Where permitted. 

A drainage stack shall be permitted to serve as a single stack vent system when sized and installed in accordance 
with Sections E.7.2 through E.7.9. The drainage stack and branch piping in a single stack vent system shall provide 
for the flow of liquids, solids, and air without the loss of fixture trap seals. 

E.7.2 Stack Size 

Drainage stacks shall be sized according to Table E.7.2. A maximum of two water closets shall be permitted to 
discharge to a 3 inch stack. Stacks shall be uniformly sized based on the total connected drainage fixture unit load 
with no reductions in size. 



2006 National Standard Plumbing Code-Illustrated *y\ 



Table E.7.2 

SINGLE STACK SIZE 



Stack Size 
(inches) 


Maximum Connected Drainage Fixture Units 




Stacks Less than 75 
Feet in Height 


Stacks 75 Feet to Less than 160 
Feet in Height 


Stacks 160 Feet or 
Greater in Height 










3 


24(2) 


NP 


NP 


4 


225 


24 


NP 


5 


480 


225 


24 


6 


1015 


480 


225 


8 


2320 


1015 


480 I 


10 


4500 


2320 


1015 


12 


8100 


4500 


2320 


15 


13,600 


8100 


4500 



1 . NP = not permitted 

2. Not more than two (2) water closets are permitted on a 3" stack. 

E.7.3 Branch Size 

Horizontal branches connecting to a single stack vent system shall be sized according to Table 1 1 .5. 1 B. 

EXCEPTIONS: 

(1) No more than one water closet within 18" of the stack horizontally shall be permitted on a 3" horizontal 
branch. 

(2) A water closet within 18" of a stack horizontally and one other fixture with up to 1-1/2 inch fixture drain 
size shall be permitted on a 3" horizontal branch when connected to the stack through a sanitary tee. 

E.7.4 Length of Horizontal Branches 

a. Water closets shall be no more than four (4) feet horizontally from the stack. 

EXCEPTION: Water closets shall be permitted to be up to eight (8) feet horizontally from the stack when 
connected to the stack through a sanitary tee. 

b. Fixtures other than water closets shall be no more than twelve (12) feet horizontally from the stack. 

c . The length of any vertical piping from a fixture trap to a horizontal branch shall not be considered it computing 
the fixture's horizontal distance from the stack. 

E.7.5 Maximum Vertical Drops From Fixtures 

Vertical drops from fixture traps to horizontal branch piping shall be one pipe size larger than the trap but not less 
than two (2) inch pipe size. Vertical drops shall be four (4) feet maximum length. Fixture drains that are not 
increased in size, or have a vertical drop exceeding 4 feet shall be individually vented. 

E.7.6 Additional Venting Required 

Additional venting shall be provided when more than one water closet is on a horizontal branch and where the 
distance from a fixture trap to the stack exceeds the limits in Section 1 2. 1 8.4. Where additional venting is required, 
the fixture(s) shall be vented by an individual vent, common vent, wet vent, circuit vent, or a combination waste 
and vent pipe. The dry vent extensions for the additional venting shall connect to a branch vent, vent stack, stack 
vent, air admittance valve, or be extended outdoors and terminate to the open air. 



422 



2006 National Standard Plumbing Code-Illustrated 



E.7.7 Stack Offsets 

Where there are no fixture drain connections below a horizontal offset in a stack, the offset does not need to be 
vented. When there are fixture drain connections below a horizontal offset in a stack, the offset shall be vented 
in accordance with Section 12.3.3. There shall be no fixture connections to a stack within 2 feet above and below 
a horizontal offset. 

E.7.8 Separate Stacks Required 

Where stacks are more than two stories high, a separate stack shall be provided for the fixtures on the lower two 
stories. The stack for the lower two stories may be connected to the branch of the building drain that serves the 
stack for the upper stories at a point that is at least 10 pipe diameters downstream from the base of the upper 
stack. 

E.7.9 Sizing Building Drains and Sewers 

The building drain and branches thereof, and the building sewer in a single stack vent system shall be sized in 
accordance with Table 1 1 .5. 1 A. 

E.8 AIR ADMITTANCE VALVES 

E.8.1 Definition 

Air admittance valve: A one-way valve designed to allow air to enter theplumbing drainage system when negative 
pressures develop in the system. The device closes by gravity, without springs or other mechanical means, and 
seals the vent terminal at zero differential pressure (no flow conditions) and also under positive internal pressure. 
The purposes of an air admittance valve are ( 1 ) to provide a method of allowing air to enter the plumbing drainage 
system without the need for a vent extended outdoors to open air, and (2) to prevent sewer gases from escaping 
into the building. 

E.8.2 Where Permitted 

E.8.2.1 Branch, circuit, common, continuous, and individual vents shall be permitted to terminate with a 
connection to an individual or branch type air admittance valve complying with ASSE 1051. Individual and branch 
type air admittance valves shall only vent fixtures that are on the same floor level and connect to a horizontal 
branch drain. 

E.8.2.2 Vent stacks and stack vents shall be permitted to terminate at a stack type air admittance valve 

complying with ASSE 1 050. 

EXCEPTIONS 

(1) Vent stacks and stack vents serving drainage stacks that exceed six (6) branch intervals in height. 

(2) Vent stacks and stack vents that serve relief vents in Section E.8. 3. 

E.8.2.3 Air admittance valves shall not be permitted in the following applications: 

a. vents for special waste drainage systems (Sections 9.4.1 and 9.4.2). 

b. vents for sewage pump or ejector sump pits. 

c. vents for pneumatic sewage ejectors. 

d. suds pressure zone venting. 

e. relief vents required by Section E.8.3.1. 



2006 National Standard Plumbing Code-Illustrated 423 



E.8.3 Relief Vents 

E.8.3.1 A relief vent shall be provided where a horizontal branch drain that is vented by one or more air 
admittance valves connects to a drainage stack more than four (4) branch intervals from the top of the stack. The 
relief vent shall connect vertically to the horizontal branch drain between the drainage stack and the most 
downstream fixture drain connection on the horizontal branch drain. Relief vents shall extend from the horizontal 
branch drain to a vent stack, stack vent, or other vent that terminates outdoors in open air. 

E.8.3.2 Relief vents shall be the full size of the horizontal branch drain that they serve, up to 3 " maximum required 

size. 

E.8.3.3 Relief vents shall be permitted to vent fixtures other than those on the horizontal branch drain being 
relieved. 

E.8.4 Installation 

E.8.4.1 Air admittance valves shall be installed in accordance with the manufacturer's instructions and Section 
E.8. 

E.8.4.2 Air admittance valves shall connect to fixture trap arms within the maximum allowable trap arm lengths 
in Table 12.8.1. 

E.8.4.3 Individual and branch type air admittance valves shall be installed at least 4 inches above the top of the 
trap arm or horizontal branch drain that they serve. 

E.8.4.4 Stack type air admittance valves shall be installed at least 6 inches above the flood level rim of the highest 
fixture served by the valve. 

E.8.4.5 Air admittance valves shall be installed in accessible locations having free movement of air to enter the 

valve. 

E.8.4.6 Air admittance valves shall not be installed in HVAC supply or return air plenums or other areas subject 
to other than atmospheric pressure. 

E.8.4.7 Air admittance valves installed in insulated attic or ceiling spaces shall be installed in free air at least six 
inches above the insulation. 

E.8.4.8 Air admittance valves shall be the same size as the vent pipe to which they are connected. 

E.8.4.9 Air admittance valves shall not be installed until all required leak tests of the drainage and vent piping 
are successfully completed. 

E.8.5 Vent to Outdoors Required 

In each plumbing drainage system vented by one or more air admittance valves, at least one vent shall extend 
outdoors to open air. 



424 2006 National Standard Plumbing Code-Illustrated 



E.8.6 Referenced Standards 

E.8.6.1 ASSE 1050-2002 Stack Air Admittance Valves for Sanitary Drainage Systems. 

E.8.6.2 ASSE 1 05 1 -2002 Individual and Branch Type Air Admittance Valves for Plumbing Drainage Systems. 



2006 National Standard Plumbing Code-Illustrated 425 



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4 ^" 2006 National Standard Plumbing Code-Illustrated 





Requirements of the 
Authority Having Jurisdiction 



F.l GENERAL 

This Code does not include specific requirements in certain cases where local practices may vary from one 
jurisdiction to another. This appendix lists those sections of this Code where the Authority Having Jurisdiction must 
establish requirements. Adopting agencies should review the sections listed under Appendix F.2 and establish 
appropriate regulations or policies. 

F.2 REFERENCES 

1 .7.2 Penalties 

1.9.8 Permit Expiration 

1.10.2 Plan Review Fees 

1.10.3 Plan Review Expiration 
1.10.5 Refunding of Fees 
1.11.5 Requests for Inspection 

Minimum earth cover for water service pipe. 

Minimum earth cover for building sewers. 

Distance for required connections to public water supplies and sewers. 

Standards and requirements for private water and sewage disposal systems. 
5.3.4: Need for building traps. 

5.4.10.c: Manhole construction standards. 

6-1-7: Point of discharge for effluent from liquid waste treatment equipment. 

7.16.6: Sloping floors to floor drains. 

9.4.3. c: Points of discharge for air conditioning condensate. 

10.9.2: Disinfecting waterpiping. 

1 1 .7.6: Use of grinder pumps. 

1 1.7.10: Use of macerating toilet systems. 

15.3.1: Testing new plumbing work. 

1 5.3.2: Testing existing sewers and drains. 

16.1: State or local requirements for private sewage disposal systems. 

Chapter 1 8 : Regulations of the AHJ for mobile home and travel trailer parks. 



2.16.1 
2.16.2 
2.19.1 
2.19.2 



2006 National Standard Plumbing Code-Illustrated 477 



F.3 EXCEPTIONS, WAIVERS, APPROVALS 

There are instances where this Code specifically permits exceptions or waivers of its requirements and the 
approval of alternative materials and methods by the Authority Having Jurisdiction. These occur throughout this 
Code. 



428 2006 National Standard Plumbing Code-Illustrated 







ppendix G 



Graywater Recycling 

Systems 



2006 National Standard Plumbing Code-Illustrated 



429 



G.1 FOREWORD 

In the United States today, regulations concerning water conservation, moratoriums on sewer connections, and 
restrictions on sewer permits are a clear indication of a growing economy restrained by a lack of available water. 
Water being a finite resource, these actions serve as a warning that without adequate planning for our future water 
needs, America is facing a critical water supply shortage. 

In virtually all major metropolitan and many suburban areas in the country, water treatment plants are over- 
loaded and many, due to neglect and deferred maintenance, are beginning to fail. Finding additional water sources 
and supplies and expanding existing water treatment plant capacity is expensive, sometimes impractical, and at 
best, involves long range planning. 

Traditionally, the municipal treatment facility has been the primary source of water disposal for single and multi- 
family residential buildings and complexes. As long term water shortages increasingly are predicted in several 
areas across the nation, water conservation becomes more of a national issue. Fortunately, alternative technical 
solutions are currently available. 

Various potentially useful and dependable water treatment and recycling technologies are being explored. One 
possible source is graywater recycling, an on-site wastewater treatment and recycling system, also known as 
"Graywater Systems". This promising technology offers a practical solution to the water shortage problem as it 
applies to plumbing installations. Graywater systems are designed to safely manage wastewater and reduce water 
consumption. Graywater systems can be used in all types of residential, commercial, institutional, and industrial 
buildings. Some graywater applications include toilet and urinal flushing, landscape irrigation, supply water for 
ornamental ponds and make-up water for cooling towers. 

G.2 DEFINITIONS 

Biological Treatment: A method of wastewater treatment in which bacterial or biochemical action is 
intensified as a means of producing an oxidized wastewater. 

Black Water: Used untreated water that is flushed down toilets and urinals. This water cannot be directly 
reused. 

Effluent: Partially or completely treated liquid waste discharge from a wastewater treatment system. 

Graywater: Used untreated water generated by clothes washing machines, showers, bathtubs and lavatories. 
It shall not include water from kitchen sinks or dishwashers. 

Reclaimed Water: Effluent from a wastewater treatment facility that has been subjected to extensive 
treatment in order to remove organic material, heavy metals, and harmful pathogens (such as bacteria, 
viruses, and protozoa). Reclaimed water is non-potable. 

Septic Tank: A water-tight receptacle that receives the discharge of a building sanitary drainage system or 
part thereof, and is designed and constructed so as to separate solids from the liquid, digest organic matter 
through a period of detention, and allow the liquids to discharge into the soil outside of the tank through a 
system of open joint or perforated piping, or a seepage pit. 

Wastewater: The combination of liquid and water-earned pollutants from residences, commercial buildings, 
industrial plants, and institutions. 



430 2006 National Standard Plumbing Code-Illustrated 



G3 APPROVED MATERIALS 

All materials, fixtures or equipment used in the installation, repair or alteration of graywater systems, shall conform 
to the standards set forth in Chapter 3 of this Code. Nothing contained herein shall prohibit the Authority Having 
Jurisdiction from imposing more stringent requirements. 

Materials not listed in Chapter 3 of this Code may be used with the approval of the Authority Having Jurisdiction 
as permitted in Section 3.1 2.2. 

G4 APPROVED INSTALLATIONS 

Prior to construction of a graywater system, the appropriate permits shall be obtained from the Authority Having 
Jurisdiction having jurisdiction. The applicant shall provide the Authority Having Jurisdiction with complete plans 
and manufacturers' recommendations of the proposed installation. 

AH pipe sizing and installation procedures shall conform to the applicable sections of this Code. Nothing shall 
preclude the Authority Having Jurisdiction from requiring more stringent compliance procedures. 

G.5 PROHIBITED INSTALLATIONS 

Surface draining graywater shall not be permitted to collect on the surface of the ground or to run off the property. 
Graywater shall not be permitted to come in direct contact with edible food sources. 

G6 ACCEPTABLE TREATMENT METHODS 

G.6.1 Nylon or Cloth Filter 

The nylon or cloth filter system typically consists of a filter bag connected to the graywater inlet pipe in a 
tank. The graywater is passed through the filter media (that collects hair and lint) and proceeds on for further 
treatment. 

G.6.2 Sand Filter 

The sand filter system consists of a sand and rock filled tank with an underdrain system. The graywater is 
poured onto splash plates and then filtered through filter media, while receiving physical and biological treat- 
ment. The filtered graywater then is collected and transported via an underdrain system for reuse. 

G.6.3 Diatomaceous Earth Filter 

Diatomaceous filters are commonly used for filtering water for swimming pools and spas. The use of this 
type of filter is primarily limited to separating solids in suspension with the use of a recirculating line. 

G.6.4 Rack or Grate Filters 

The primary function of the rack or grate filter is to remove particle matter from the graywater. 

G.6.5 Collection and Settling 

Commonly found in septic systems, whereby solids flow into the tank and are permitted to settle to the bottom 
forming a sludge layer. 

G.6.6 Biological Treatment Units 

Typically a process in which solids are separated through the use of three chambers. Pre-settling, aeration, 
and final settling separate the solids while allowing biological treatment prior to reuse. This type of treatment 
is usually found in large commercial applications. 



2006 National Standard Plumbing Code-Illustrated 431 



G.6.7 Reverse Osmosis 

A process involving treatment of the graywater by a reverse osmosis unit. 

G.6.8 Physical/Chemical Treatment 

Graywater is processed through a rapid mix tank in which polymer and activated carbon are added. The 
treated graywater is then passed through a settling tank in which sludge is removed. The graywater then 
goes on to numerous filters for further treatment. 

G.7 DISINFECTION TECHNIQUES 

Ultraviolet Irradiation 

Ozone 

Chlorine 

Iodine 

G.8 IRRIGATION METHODS 

Mini-Leachfield 
Drip Irrigation 

G9 PROTECTION OF THE POTABLE WATER SUPPLY 

A graywater system shall be designed, installed and maintained to prevent contamination from non-potable liquids, 
solids or gases into the potable water supply through cross-connections. 

In all buildings where dual water systems are installed, one potable water and one non-potable water, each 
system shall be identified either by color marking or metal tags, or other appropriate method as approved by the 
Authority Having Jurisdiction having jurisdiction. Each outlet on the non-potable water line that may be used for 
drinking or domestic puiposes shall be posted: DANGER—UNSAFE WATER. 

The potable water supply shall be protected from backflow and back-siphonage by an approved method of 
cross-connection control required by Sections 10.4 and 10.5 of this Code. Nothing contained herein shall prohibit 
the Authority Having Jurisdiction from requiring more stringent requirements. 

G.10 TESTING 

All applicable sections of this appendix shall conform to the body of this Code. Installation of the graywater 
system shall conform in all aspects to the manufacturers recommended installation procedures. 

Systems shall be tested and comply with the Authority Having Jurisdiction. Piping, valves, and fittings shall be 
tested in compliance with Chapter 15 of this Code. 

Gil MAINTENANCE 

The graywater system shall be maintained in accordance with the manufacturers recommended maintenance 
instructions. 

Nothing in this Appendix shall preclude the Authority Having Jurisdiction from requiring additional maintenance 
procedures. 



■"2 2006 National Standard Plumbing Code-Illustrated 



INSTALLATION OF 

MEDICAL GAS 

AND VACUUM PIPING 

SYSTEMS 



(Refer to NFPA 99-2005 or NFPA 99C-2005) 



2006 National Standard Plumbing Code-Illustrated 



433 



Blank Page 



434 2006 National Standard Plumbing Code-Illustrated 














Fixture Unit Value 
Curves for Water Closets 



2006 National Standard Plumbing Code-Illustrated 



435 



1.1 DRAINAGE FIXTURE UNITS — WATER CLOSETS 



a 

3 



c 

3 



10 

s 

6 

4 
2 




Chart 1.1(a) 

Drainage Fixture Units - Water Closets 
Heavy Use Assembly 




0.2 0.4 0.6 0.8 1 12 1.4 1.6 1.8 

Flush Volume (Gallons) 



• Gravity q=1 6 — J a— Valve q=1 92 — •— Press Tank q=32 



Chart 1.1(b) 

Drainage Fixture Units - Water Closets 
Other than Dwellings 




■+- 



-+- 



•+- 



-+- 



-f- 



0.2 



0.4 0.6 0.8 1 1.2 1.4 

Flush Volume (Gallons) 



1.6 



1.8 



-*— Gravity q=16 



Valve q=1 92 — #-* Press Tank q=32 



10 

8 



a 


6 


£ 


4 


3 




X 


2 






(A 






Chart 1.1(c) 

Drainage Fixture Units - Water Closets 
Dwellings 



■+- 



-+- 




0.2 



0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 

Flush Volume (Gallons) 



-*— Gravity q=16 



Valve q=1 92 



•Press Tank q=32 



©1994 Stevens Institute ofTecknology 



436 



2006 National Standard Plumbing Code-Illustrated 



1.2 WATER SUPPLY FIXTURE UNITS — WATER CLOSETS 



Chart 1.2(a) 

Water Supply Fixture Units - Water Closets 
Heavy Use Assembly 




0.2 0.4 0.6 0.8 1 1.2 

Flush Volume (Gallons) 



1.4 



1.6 



1.8 



Press Tank 
q=1.5 



Gravity q=2.4 



Valve q=20 



Valve q=24 



s 



Chart 1.2(b) 

Water Supply Fixture Units - Water Closets 
Dwellings and other Services 



10 
9 
8 
7 



5 4 




•+• 



+ 



-+- 



0.2 



0.4 



0.6 0.8 1 1.2 

Flush Volume (Gallons) 



1.4 



1.6 



1.8 



Press Tank 
q=1.5 



Gravity q=2.4 



Valve q=20 



Valve q=24 



©1994 Stevens Institute of Technology 



2006 National Standard Plumbing Code-Illustrated 



437 



Blank Page 



**^" 2006 National Standard Plumbing Code-Illustrated 



Sizing Grease 
interceptors 



2006 National Standard Plumbing Code-Illustrated 



439 



One Acceptable Method of Sizing Grease Interceptors 

Waste waters that are not grease laden and do not require separation shall not be discharged into any grease 
interceptor. 

1 . Determine the cubic content of the fixture, equipment or sink compartment that will produce the grease 
laden waste water that will require separation. Length x Width x Depth 

2. Determine the capacity in gallons. 1 gallon=231 cubicinches. 

3. Determine the actual drainage load. 

a. The fixture is usually filled to about 75% of capacity with water. 

b. The itemsbeing washed displace about 25% of the fixture content. 

c. Actual drainage load= 75% of the fixture, equipment or sink compartment. 

4. Determine the drainage rate. 

a. In general, good practices dictate a one minute drainage period. 

b. However where conditions permit, a 2-minute drainage period is acceptable. 

c. Drainage rate = Drainage period is the actual time required to completely drain the unit. 

5 . Determine the flow rate. 

Flow rate = Actual drainage load (divided by) Drainage rate. 

6. Select trap size based on calculated drainage rate and flow rate. 



440 2006 National Standard Plumbing Code-Illustrated 








Flow In 
Sloping Drains 



2006 National Standard Plumbing Code-Illustrated 



441 



Flow in Sloping Drains 

Tables K-l and K-2 list flow rates in gallons per minute and velocities in feet per second for various 
size drains at various slopes. Table K-l is based on fairly rough pipe. Table K-2 is based on smooth 
pipe. 

The minimum flow velocity to achieve scouring in horizontal sanitary drain lines is two (2) feet per 
second. For this reason, based on Table K-2 for smooth pipe, drains that are 2 inches and smaller 
must be sloped at not less than 1/4 inch per foot. Drains that are 3" size and larger can be sloped at 1/ 
8 inch per foot. 

Even at 1/4" per foot slope, the uniform velocity in drains that are 1-1/4", 1-1/2", and 2" size is less 
than 2 feet per second. Either the slope should be increased or the length of such drains should be 
kept to a minimum so that the entrance velocity will provide scouring for the short distance involved. 

Tables K-I and K-2 are based on the Manning Formula for 1/2 full pipe. For full flow, multiply the 
flow by 2.00 and the velocity by 1.00. For 1/4 full flow, multiply the flow by 0.274 and the velocity 
by 0.701. For 3/4 full flow, multiply the flow by 1.82 and the velocity by 1.13. 

In Table K-l, which is based on fairly rough pipe with "n" = 0.015, for smoother pipe, multiply the flow 
and velocity by 0.015 and divide by the "n" value of the smoother pipe. 

Horizontal sanitary drain and waste pipes are sized to be one-half (1/2) full under design loads. 
Horizontal storm drains are sized to run full under design loads. 

Table 11.5.1A "Building Drains and Sewers" and the horizontal piping in Table 11. 5. IB "Horizontal 
Fixture Branches and Stacks" is based on Table K-2 for smooth pipe. 

Table 13.6.2 "Size of Horizontal Storm Drains" is based on Table K-I for fairly rough pipe, adjusted for 
full flow. 



442 



2006 National Standard Plumbing Code-Illustrated 



Table K-l 

APPROXIMATE FLOW RATES AND VELOCITIES IN SLOPING DRAINS 

(FOR FAIRLY ROUGH PIPE n = 0.015) 

Flowing Half Full 





1/16 in./ft. slope 


1/8 in./ft. slope 


1/4 in./ft. slope 


1/2 in./ft. sIoDe 


Actual inside 
diameter of 
pipe - inches 


Flow 
gpm 


Vel. 
fps 


Flow 
gpm 


Vel. 
fps 


Flow 
gpm 


Vel. 
fps 


Flow 
gpm 


Vel. 
fps 


1.250 










2.40 


1.25 


3.40 


1.77 


1.375 










3.10 


1.35 


4.38 


1.91 


1.500 










3.90 


1.41 


5.52 


1.99 


1.625 










4.83 


1.50 


6.83 


2.12 


2 










8.41 


1.73 


11.9 


2.44 


3 






17.5 


1.60 


24.8 


2.26 


35.0 


3.20 


4 


26.7 


1.36 


37.7 


1.92 


53.4 


2.72 


75.5 


3.84 


5 


48.4 


1.58 


68.4 


2.23 


96.8 


3.16 


137 


4.47 


6 


78.7 


1.79 


111 


2.53 


157 


3.57 


223 


5.05 


8 


169 


2.17 


240 


3.06 


339 


4.33 


479 


6.13 


10 


307 


2.51 


435 


3.55 


615 


5.02 


869 


7.10 


12 


500 


2.84 


707 


4.01 


999 


5.67 


1413 


8.02 


15 


906 


3.29 


1281 


4.66 


1812 


6.59 


2563 


9.32 



2006 National Standard Plumbing Code-Illustrated 



443 



Table K-2 
APPROXIMATE FLOW RATES AND VELOCITIES IN SLOPING DRAINS 

(FOR SMOOTH PIPE n = 0.011) 
Flowing Half Full 



Actual inside 
diameter of 
pipe - inches 


1/16 in./ft. slope 


1/8 in./ft. slope 


1/4 in./ft. slope 


1/2 in./ft. slope 


Flow 
gpm 


Vel. 
fps 


Flow 

gpm 


Vel. 
fps 


Flow 
gpm 


Vel. 
fps 


Flow 
gpm 


Vel. 
fps 


1.250 










3.27 


1.71 


4.63 


2.42 


1.375 










4.22 


1.84 


5.97 


2.60 


1.500 










5.32 


1.92 


7.53 


2.72 


1.625 










6.86 


2.04 


9.32 


2.89 


2 










11.5 


2.35 


16.2 


3.33 


3 






23.9 


2.18 


33.8 


3.08 


47.8 


4.36 


4 


36.4 


1.85 


51.5 


2.62 


72.8 


3.71 


103 


5.24 


5 


66.0 


2.15 


93.3 


3.05 


132 


4.31 


187 


6.09 


6 


107 


2.44 


152 


3.44 


215 


4.87 


303 


6.89 


8 


231 


2.95 


327 


4.18 


462 


5.91 


654 


8.36 


10 


419 


3.42 


593 


4.84 


838 


6.84 


1185 


9.68 


12 


681 


3.87 


964 


5.47 


1363 


7.73 


1927 


10.94 


15 


1236 


4.49 


1747 


6.35 


2471 


8.99 


3495 


12.71 



444 



2006 National Standard Plumbing Code-Illustrated 



mum/mm 




ssaSSSsglSSsiw: 







a?ss?««i 







An Acceptable Brazing 
Procedure for General 

Plumbing 



2006 National Standard Plumbing Code-Illustrated 



445 



The following is extracted and edited with permission from Chapter VII of The Copper Tube Handbook 
published by the Copper Development Association. This brazing procedure is acceptable for general 
plumbing work. Refer to NFPA 99 or NFPA 99C for brazing medical gas piping. 

Introduction 

Strong, leak-tight brazed connections for copper tube may be made by brazing with filler metals which melt at 
temperatures in the range between 1 100 F and 1 500 F, as listed in Table 12. Brazing filler metals are sometimes 
referred to as "hard solders" or "silver solders." These confusing terms should be avoided. 

The temperature at which a filler metal starts to melt on heating is the solidus temperature; the liquidus tempera- 
ture is the higher temperature at which the filler metal is completely melted. The liquidus temperature is the 
minimum temperature at which brazing will take place. 

The difference between solidus and liquidus is the melting range and may be of importance when selecting a filler 
metal. It indicates the width of the working range for the alloy and the speed with which the alloy will become 
fully solid after brazing. Filler metals with narrow ranges, with or without silver, solidify more quickly and, there- 
fore, require more careful application of heat. The melting ranges of common brazing metals are shown in Figure 

8a. 

Brazing Filler Metals 

Brazing filler metals suitable for joining copper tube are of two classes: 

(1) alloys that contain phosphorus (the BCuP series) and 

(2) alloys containing a high silver content (the BAg series) 

The two classes differ in their melting, fluxing and flowing characteristics and this should be considered in selec- 
tion of a filler metal. (See Table 12.) For joining copper tube, any of these filler metals will provide the necessary 
strength when used with standard solder-type fittings or commercially available short-cup brazing fittings. 

Fluxes 

The fluxes used for brazing copper joints are different in composition from soldering fluxes. The two types cannot 
be used interchangeably. 

Brazing fluxes are water based, whereas most soldering fluxes are petroleum based. Similar to soldering fluxes, 
brazing fluxes dissolve and remove residual oxides from the metal surface, protect the metal from re-oxidation 
during heating and promote wetting of the surfaces to be joined by the brazing filler metal. 

Fluxes also provide the craftsman with an indication of temperature. If the outside of the fitting and the heat- 
affected area of the tube are covered with flux (in addition to the end of the tube and the cup), oxidation will be 
prevented and the appearance of the joint will be greatly improved. 

The fluxes best suited for brazing copper and copper alloy tube should meet AWS Classification FB3-A or FB3-C 
as listed in Table 4. 1 of the AWS Brazing Handbook. Figure 9 , illustrates the need for brazing flux with different 
types of copper and copper-alloy tube, fittings and filler metals when brazing. 



446 2006 National Standard Plumbing Code-illustrated 



Assembling 

Assemble the joint by inserting the tube into the socket hard against the stop and turn if possible. The assembly 
should be firmly supported so that it will remain in alignment during the brazing operation. 

Applying Heat and Brazing 

Step one: Apply heat to the parts to be joined, preferably with an oxy-fuel flame. Air-fuel is sometimes used on 
smaller sizes. A neutral flame should be used. Heat the tube first, beginning about one inch from the edge of the 
fitting, sweeping the flame around the tube in short strokes at right angles to the axis of the tube. 

It is very important that the flame be in motion continuously and not remain on anyone point long enough to 
damage the tube. The flux may be used as a guide as to how long to heat the tube; continue heating the tube until 
the flux becomes quiet and transparent like clear water. The behavior of flux during the brazing cycle is described 
in Figure 8b . 

Step two: Switch the flame to the fitting at the base of the cup. Heat uniformly, sweeping the flame from the 
fitting to the tube until the flux on the fitting becomes quiet. Avoid excessive heating of cast fittings. 

Step three: When the flux appears liquid and transparent on both the tube and fitting, start sweeping the flame 
back and forth along the axis of the joint to maintain heat on the parts to be joined, especially toward the base of 
the cup of the fitting. The flame must be kept moving to avoid melting the tube or fitting. 

Step four: Apply the brazing filler metal at a point where the tube enters the socket of the fitting. When the 
proper temperature is reached, the filler metal will flow readily into the space between the tube and fitting socket, 
drawn in by the natural force of capillary action. 

Keep the flame away from the filler metal itself as it is fed into the joint. The temperature of the tube and fitting 
at the joint should be high enough to melt the filler metal. 

Keep both the fitting and tube heated by moving the flame back and forth from one to the other as the filler metal 
is drawn into the joint. 

When the joint is properly made, a continuous fillet of filler metal will be visible completely around the joint. Stop 
feeding as soon as you see that fdlet. Table 1 1 is a guide to estimating how much filler metal will be consumed. 

For 1-inch tube and larger it may be difficult to bring the whole joint up to heat at one time. It frequently will be 
found desirable to use a multiple-orifice torch tip to maintain a proper temperature over large areas. A mild 
preheating of the whole fitting is recommended for larger sizes. Heating then can proceed as outlined in the steps 
above. 

Horizontal and Vertical Joints 

When brazing horizontal joints, it is preferable to first apply the filler metal at the bottom, then the two sides, and 
finally the top, making sure the operations overlap. On vertical joints it is immaterial where the start is made. If 
the opening of the socket is pointing down, care should be taken to avoid overheating the tube, as this may 



2006 National Standard Plumbing Code-Illustrated 447 



cause the brazing filler metal to run down the outside of the tube. If this happens, take the heat away and allow 
the filler metal to set. Then reheat the cup of the fitting to draw up the filler metal . 

Removing Residue 

After the brazed joint has cooled the flux residue should be removed with a clean cloth, brush or swab using 
warm water. Remove all flux residue to avoid the risk of the hardened flux temporarily retaining pressure and 
masking an imperfectly brazed joint. Wrought fittings may be cooled more readily than cast fittings, but all fittings 
should be allowed to cool naturally before wetting. 

General Hints and Suggestions 

If the filler metal fails to flow or has a tendency to ball up, it indicates oxidation on the metal surfaces or insuffi- 
cient heat on the parts to be joined. If the tube or fitting start to oxidize during heating there is too little flux. If the 
filler metal does not enter the joint and tends to flow over the outside of either member of the joint, it indicates that 
one member is overheated or the other is under heated. 

Testing 

Test all completed assemblies for joint integrity. Follow the testing procedure prescribed by applicable codes 
governing the intended service. 

Table 12.Filler Metals for Brazing 



| AWS 
Classification 1 

1 „„,..,„„ 


Principal Elements 


Temperature F 


Silver j 


Phosphorus | Zinc 


Cadmium j 


Tin 


Copper 


Solidus 


Liquidus 


J BCup-2 


\ 


7.00-7.5 | 


i 


; 


Remainder 


1310 


1460 


J BCup-3 


4.8-5.2 { 


5.8-6.2 | 


: 


- 


Remainder 1 


1190 


1495 


j BCup-4 


5.8-6.2 j 


7.0-7.5 \ - ! 

....,., .,,,..._,,, -\ . . .. I 


- 


Remainder 


1190 


1325 


BCup-5 


14.5-15.5 


ij 
4.8-5.2 j - 


- 


- 


Remainder 


1190 


1475 


BAg-P 


44-46 j 


: 14-18 j 

,j:i 


23-25 2 


- 


14-16 


1125 


1145 


BAg-2 2 


34-36 j 


I 


19-23 : 


17-19 2 


\ 


25-27 


1125 


1295 


BAg-5 


44-46 \ 




23-27 


- 


- \ 


29-31 


1225 


1370 


j BAg-7 


55-57 ! 


\ 


15-19 j 


i 


4.5-5.5 


21-23 


1145 


1205 



'ANS1/AWS A5.8 Specification for Filler Metals for Brazing 

2 WARNING: BAgl and BAg2 contain cadmium. Heating when brazing can produce highly toxic fumes. 

CAUTION: Avoid breathing fumes - use adequate ventilation. Refer to ANSI/ASC Z49.1 Safety in Welding and Cutting. 



448 



2006 National Standard Plumbing Code-Illustrated 



Figure 8. Melting Temperature Ranges for Copper and Copper Alloys, Brazing Filler Metals, 

Flux and Solders 



8a. 



mmf m 






1SQ0F 






1000 f 



500 F 



HEiTMSRAMSE 
1310-1 W, Red Brass 



166M710,YsB0« Brass 

iRAZINS TEMPERATU8E RANS6 

1350 1550. BCiiP-2 Copper Phes. 
13t 15S0.BS S3 CDpp«fPhK, 
130Q-145<< Bl a J L-.jps. Phcs 
13*1500 BC'JP-S nnpprPhos 
1145-1400, BA§4 Sfer 
1 15-1550 >«-f-2 Silver 
1370-1550, BAjhS Ster 
f 285-1 *»,B%7 Silver 



8b. 



MELTING RANGE-SOLOERS 

452-464, 95-5 T.n ftnhrr . i v 
361-421, 50-10 JWim 




20CI3F 



1500 F 
1000 f 

5MF 






J&www 



Spsc«!fta?tagte«f 
fi% Prefect f& Here 



Standard gazing Ftaes 
Prated to Here 



forfeior distant mm*) 



FluxGI«arasrfQ»t 

flux Bigtns to Mill 
FtaB*M#$ 



\ 



Water Soft QUI of fax 

Room Temspswture 




2006 National Standard Plumbing Cade-Illustrated 



449 



Figure 9. Brazing Flux Recommendations 




■mm 



BCuP FITTING 
BRASS / 



FILLER 
METAL 

COPPER 



CAST 



BRASS 



WROUGHT 8*0 





WROW3HT @A§ 



cast 



»% 



8Ag 



450 



2006 National Standard Plumbing Code-Illustrated 



Table 1 1 . Typical Brazing Filler Metal Consumption 





Tube, 
nominal 

or 

standard 

size, 

inches 


Filler Metal Length, inches 


Average 
weight per 
100 joints, 

pounds 1 




1/16 inch 
wire 


1/8 inch x 0.050 
inch rod 


3/32 inch 
wire 


1/8 inch 
wire 




v 4 


v 2 [ 


% 


% 


v. | 


.04 




% 


% 


% 


\ 


7 4 [ 


.06 




> i 


1% 


% 


^ i 


3 / 8 


.10 




5 / ! 

'8 


l 5 /s j 


% 


5 / 8 ; 


v 2 


.15 




u 


2% 


I'/s 


1 i 


n % 


.21 




1 


3'/ 2 


l 3 / 4 


i 5 / 8 


7 / 8 


.32 




i'/ 4 


4V 2 


2 7, 


2 


i7 4 


.42 


:■ 


i \ 


i 


3 


2% 


1 v 2 


.56 




2 


- 


4 3 / 4 


4% 


2 7 2 


.90 




}% f 


- 


6V 2 


5% ; 


3 3 / g 


1.22 




3 


- 


8% 


7 7 / 8 


47 2 j 


1.64 




3V 2 ( 


5 


11 v 2 


10 7 2 = 


5 7 / 8 j 


2.18 




4 


! 


14 7 / g 


13 V 2 


7% 


2.81 


\\ 5 


i 


22 5 / 8 


20 V 2 


11% 


4.30 




6 


! 


31 V 2 


28 7 2 j 


16 


5.97 ; 




8 


- 


53 V 2 


48 7 2 


27 3 / 8 


10.20 


if 10 

1, 




67 V 4 


61 


34 7 4 j 


12.77 




12 


j 


90 7 2 


82 


46 7 8 j 


17.20 



Footnote 1 

The amount of filler material indicated is based on an average two-thirds penetration of the cup and with no provision 
for a fillet. For estimating purposes, actual consumption may be two to three times the amounts indicated in this table, 
depending on the size of the joints, method of application and level of workmanship. 



NOTE: 



1090 inches of 1/1 6 inch wire = 1 pound 

534 inches of 1/8 inch x .050-inch wire = 1 pound 

484 inches of 3/32 inch wire = 1 pound 

268 inches of 1/8 inch wire = 1 pound 



2006 National Standard Plumbing Code-Illustrated 



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452 2006 National Standard Plumbing Code-Illustrated 









Accessible: 

Definition of, 1.2 

Backflow preventers, 10.5.5 

Backwater valves, 5.5.2 

Expansion joints, 4. 1 .3 

Fixture, appliance and equipment 
valves, 10. 12.4. a 

Flushometer valves, 7.19.5 

Liquid waste treatment equipment, 6.1.6 

Sump pits, 11.7.1 

Valves in multi-dwelling units, 1 0. 1 2.4.d 

Water hammer arrestors, 10. 14. 7. c 

Water supply control valves, 10.12.9 
Adopting Agency: 

Definition of, 1.2 
Authority Having Jurisdiction: 

Definition of, 1.2 

Requirements for, Appendix F 
Air Break: 

Definition of, 1.2 

Air conditioning equipment, 9.1.10 

Commercial dishwashing machines, 7. 15.4 

Drinking fountains, 9.1.9 

Food handling areas, 9.1.5 

Potable clear water wastes, 9.1.8 

Walk-in coolers, 9.1.6 

Walk-in freezers, 9.1.6 
Air Chambers: 

Definition of, 1.2 
Air Gap (drainage): 

Definition of, 1.2 

Air conditioning equipment, 9.1.10 

Aspirators, 14.13 

Bedpan steamers, 14.10.2 

Commercial dishwashing machines, 7. 15.4 

Drain outlets, 9.1.2 

Drinking fountains, 9.1.9 

Drinking water treatment units, 7.22, 10.18.2 

Food handling areas, 9.1.5 

Indirect waste pipes, 9.1.2 

Medical equipment, 9. 1 .7 

Minimum for fixtures, Table 10.5.2 



Potable clear water wastes, 9.1.8 

Reliefvalve discharge piping, 10.16.6.d 

Sterilizers, 14.10.2 

Swimming pools, 9.1.11 
Air Gap (water distribution): 

Definition of, 1.2 

Automatic clothes washers, 7.13.1 

Below rim supply to tank or vat, 10.5.7 

Domestic dishwashers, 7.15.1 

Over-rim tub filler spout, 7.8.4 

Requirements for, 10.5.2 
Anchors; 

See Supports 
Anti-scald valve: 

See Water Temperature Control Valve 
Approval of Alternate Materials: 

Requirements for, 3.12 
Approval: 

Definition of, 1.2 
Area Drain: 

Definition of, 1.2 
Aspirator: 

Definition of, 1.2 
Backfilling: 

Requirements for, 2.6.3, 2.6.4 
Backflow (drainage): 

Definition of, 1.2 
Backflow (water distribution): 

Definition of, 1 .2 
Backflow Preventers: 

Definition of, 1 .2 

Approval of, 10.5.4 

Installation of, 10.5.5 

Maintenance and testing of, 10.5.6 

Required types, 10.5.3 

Standards for, Table 3.1.3 Part IX 
Backflow Prevention: 

Appliances, 10.5.1 

Carbonated beverage dispensers, 10.5.8 

Domestic water heat exchangers, 10.5.11 

Fire protection systems, 10.5.9 

Hose connections, 10.5.12 



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453 



Irrigation systems, 10.5.10 

Lawn sprinklers, 10.5.10 

Plumbing fixtures, 10.5.1 

Special equipment, 10.5.13 

Tanks and vats, 10.5.7 

Water supply outlets, 10.5.1 
Backpressure backflow: 

Definition of, 1 .2 
Back Siphonage: 

Definition of, 1.2 
Backwater Valve: 

Definition of, 1.2 

Posted notice, 5.5.3 
Baptistries: 

Backflow protection, 7.18 
Bar Sinks: 

Requirements for, 7.1 1.2 
Basic Design Circuit (BDC): 

Explanation of, B.9.3 
Bathroom Group: 

Definition of, 1.2 

Drainage fixture units (DFU), Table 1 1 .4. 1 

Stack venting, 12.11 

Water supply fixture units (WSFU), Table 

10.14.2.A 

Wet venting, 12.10 
Bathtubs: 

Requirements for, 7.8 
Battery of Fixtures: 

Definition of, 1.2 
Bedding 

Under pipes in trenches, 2.6.1 
Bidets: 

Requirements for, 7.7 
Branch Interval: 

Definition of, 1.2 
Building Classification: 

Definition of, 1 .2 
Building Sanitary Drain: 

Definition of, 1.2 

Materials, 3.5.2 

Required size, Table 1 1.5. LA 
Building Storm Drain: 

Definition of, 1.2 

Materials, 3.7.3 

Required size, 13.6.2 
Building Sanitary Sewer: 

Definition of, 1.2 

Materials, 3.5.3 



Required size, Table 1 1 .5 . 1 .A 

Separation from water service, 10.6.1 
Building Storm Sewer: 

Definition of, 1.2 

Materials, 3.7.4 

Required size, 13.6.2 
Building Subdrains: 

Definition of, 1.2 

Sump pits and pumps, 11.7 

Venting, 11.7.4 
Building Traps: 

Definition of, 1.2 

Where required, 5.3.4 
Cesspool: 

Definition of, 1 .2 
Chemical Waste: 

See Special Wastes 

Treatment of, 9.4.1 
Cleanouts: 

At base of stacks, 5.4.5 

At junction of bldg drain and bldg sewer, 5.4.6 

Direction of opening, 5.4.7 

In building sewers, 5.4.2 

In concealed piping, 5.4.4 

Manholes, 5.4.10 

Prohibited connections to, 5.4.8 

Required size, 5.4.9 

Spacing, 5.4.1 
Clear Water Wastes: 

Definition of, 1.2 
Clinical Sinks: 

Definition of, 1.2 

Local vents for, 14.9 

Requirements for, 14.8.1 
Clothes Washers: 

Required compliance, 7.13 
Code: 

Definition of, 1.2 
Combination Fixtures: 

Definition of, 1.2 
Combination Waste and Vent Systems: 

Definition of, 1.2 

Requirements for, 12.17 
Conductors (storm water): 

Definition of, 1.2 

Connection to combined sewer, 13.4.3 

Improper use, 1 3.4. 1 

Required size, 13.6.1 



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Continuous or Intermittent Drain Flow: 

Conversion to DFU, 1 1 .4.2 
Corrosive Fill: 

Protection of pipes, 2.9.2 
Corrosive Wastes: 

Treatment of, 9.4. 1 
Critical Level: 

Definition of, 1.2 
Of backflow preventers, 10.5.5 
Cross Connection: 

Definition of, 1.2 
Control, 10.4.3 
Cross Connection Control 
Program for, 10.4.3 
Cutting and Notching: 

Structural members, 2.9.3 
Day Care Center: 

Definition of, 1.2 
Day Nursery: 

Definition of, 1.2 
Dead Ends: 

Definitions, 1.2 
Avoidance, 2.23 
Decorative Fountains : 

Backflow protection, 7. 1 8 
Defective Plumbing: 

Testing or inspecting, 15.7 
Definitions: 

Code terms, Chapter 1 
Mobile home park, 18.1 
Travel trailer park, 18.1 
Demand (water): 

Estimating procedure, B.5 
Sizingpiping, 10.14.3 
Developed Length: 

Definition of, 1.2 
Diameter: 

Definition of, 1.2 
Dilution Tanks: 

Requirements for, 6.6 
Directional Changes: 

In drainage piping, 2.3 
Discharge Rates: 

In sloping drains, Appendix K 
Dishwashing Machines : 

Requirements for, 7.15 
Disinfection: 

Of potable water systems, 10.9 



Disposal Fields: 

Size and spacing, 16.9.3 
Distribution Box: 

For individual sewage disposal system, 16.9 
Domestic Sewage 

Definition of, 1.2 
Double Check Valve Assembly 
Definition of, 1.2 
Installation of, 10.5. 5. d 
Maintenance of, 10.5.6 
Testing of, 10.5.6 
Where required, 10.5.3 
Downspout (rain water): 

See Leader 
Drainage Fixture Unit (DFU) 

See Fixture Unit, Drainage 
Drainage Piping: 

See Drainage System 
Drainage System: 

Definition of, 1 .2 
Drainage System, Building Gravity: 

Definition of, 1 .2 
Drainage System, Sanitary 

Branch connections (near base of stacks), 11.9 
Branch connections (to offsets), 11.10 
Building sewers, 1 1 .2 
Ejectors and pumps, 11.7 
Fixture units (DFU), 1 1 .4 
Offsets in piping, 11.6 
Pipe sizing, 1 1 .5 
Piping materials, 3.5 
Slope of piping, 11.3.1 
Suds pressure zones, 11.11 
Sump pits, 11.7 
Drainage System, Storm: 

Air conditioning condensate, 13.8 
Areaway drains, 13.1.6 
Backwater valves, 13.1.12 
Combined sewer, 13.4.3, 13.4.4 
Continuous flow, 13.1.11 
Controlled flow system, 13.9 
Foundation drains, 13.1.5 
Parking garages, 13.1.8 
Pipe sizing, 13.6 
Piping materials, 3.7 
Prohibited connections, 13.1.2 
Protection of leaders, 13.4.2 
Roof drainage, primary, 13.1.10.1 
Roof drainage, secondary, 13.1.10.2 



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Roof drains, 13.5 

Service garages, 13.1.8 

Sewers, 13.1.3 

Traps, 13.3 

Vertical walls, 13.1.10.3 

Window well drains, 13.1.7 
Drinking Fountains : 

Compliance, 7. 12.1 

Indirect waste discharge, 9.1.9 

Prohibited locations, 7. 12.2 
Drinking Water Facilities: 

Required number of: Table 7.21 . 1 
Dry Well: 

Definition of, 1.2 
DWV (drain- waste- vent): 

Definition of, 1.2 
Effective Opening: 

Definition of, 1.2 
Ejector (sewage): 

Building subdrains, 1 1.7.1 

For individual fixtures, 1 1.7.9 

Grinderpumps, 11.7.6 

High water alarms, 1 1.7.11 

Macerating toilet systems, 11.7.10 

Pneumatic, 11.7.7 

Requirements for, 1 1 .7.8 

Sump pits, 11.7.1 

Venting subdrains, 1 1 .7.4 
Equipment: 

Condemned, 2. 15 

Used, 2.14 
Equivalent Length: 

Definition of, 1.2 

Of valves and fittings, B.9.7 
Erosion (pipe): 

Corrosion, B. 6. 3 
Existing Buildings: 

Code compliance, 3.12.1 
Existing Work: 

Definition of, 1.2 
Expansion Joints: 

Access to, 4.1.3 
Exposure of Work: 

For testing and approval, 15.1 
Family: 

Definition of, 1.2 
Ferrous Pipe and Fittings: 

Standards, Table 3.1.3, Part I 



Filter (sewage): 

See Sand Filter 
Fixtures (plumbing): 

Definition of, 1.2 

Accessible use, 7.2 

Access for cleaning, 7.3.3 

Access for use, 7.21.3 

Air gaps for, 10.5.2 

Automatic clothes washers, 7.13 

Back-to-back, 2.3.3 

Bathtubs, 7.8 

Bidets, 7.7 

Circular wash fountains, 7.6.5 

Clearances required, 

Combination bath/showers, 

DFU load values, 11.4 

Dishwashing machines, 7. 1 5 

Drinking fountains, 7.12 

Emergency eyewash stations, 7.24 

Emergency showers, 7.24 

Floor drains, 7.16 

Flushing devices, 7.19 

Food Waste Grinders, 7.14 

Garbage can washers, 7.17 

Group-type wash fountains, 7.6.5 

Group-type wash sinks, 7.6.5 

In correctional institutions, 7.20 

In detention centers, 7.20 

In facilities serving customers, 7.21 .7 

In food service areas, 7.21.8 

In special occupancies, 7.21.6 

Installation of, 7.3 

Lavatories, 7.6 

Minimum number of, 7 . 2 1 

Occupant load for, 7.21 .2 

Omission of, 7.2 1.5 

Prohibited urinals, 7.5.4 

Prohibited water closets, 7.4.7 

Separate toilet facilities, 7.21.4 

Showers, 7.10 

Sinks, 7. 11 

Spa and hot tub safety, 7.23 

Special installations, 7.18 

Substitution of, 7.21.5 

Standards for, 7.1 

Trench drains, 7.16 

Urinals, 7.5 

Water closets, 7.4 



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2006 National Standard Plumbing Code-Illustrated 



Water coolers, 7.12 
Water treatment systems, 7.22 
Whirlpoolbaths,7.9 
WSFU load values, Table 10.4.2.A 
Fixture Branch (drainage): 
Definition of, 1.2 

Minimum size underground, 1 1.5.5 
Sizing, 11.5.3 
Fixture Drain: 

Definition of, 1.2 
Fixture Supply Branch: 
Definition of, 1.2 
Flow rates for sizing, 10.14.2 
Minimum size, 10.14.2 
Fixture Traps: 

General requirements, 5.3 
Separate for each fixture, 5.1 
Size, 5.2 
Fixture Unit (drainage DFU): 
Definition of, 1.2 
Converting GPM to DFU, 1 1 .4.2 
For bathroom groups, Table 1 1 .4. 1 
For individual fixtures, Table 11.4.1 
Fixture Unit (water supply WSFU): 
Definition of, 1.2 

Converting WSFU to GPM, Table 10.14.2.B 
For bathroom groups, Table 1 1 . 14.2. A 
For individual fixtures, Table 1 1.14.2.A 
For kitchen groups, Table 1 1 . 14.2. A 
For laundry groups, Table 1 1 . 14.2.A 
Flashing: 

Roof drains, 13.5.4 
Vent terminals, 12.4.2 
Vent through roof, 4.5 
Flood Level Rim: 

Definition of, 1.2 
Flooded: 

Definition of, 1.2 
Floor Drains: 

Requirements for, 7.16 
FloorFlanges: 

For water closets, 3.3.4 
Water closet connections, 2.22 
Flow Pressure: 

Definition of, 1.2 
Flow Rates (drainage): 

In sloping drains, Appendix K 
Flow Rates (water): 



Based on pressure drop, Table B.9.8 
Based on velocity, Tables B.7.3 
For fixtures, 10.14.2 
Flushing Devices: 

Flush tanks, 7.19.3 
Flushometer tanks, 7.19.4 
Flush ometer valves, 7.19.5 
Food Handling Areas: 

Indirect wastes, 9.1.5 
Requirements for, 2.25 
Food Waste Grinders: 

Into grease interceptor, 6.2.3 
Requirements for, 7.14 
With sink and dishwasher, 7. 15.3 
Footings: 

Protection of, 2.17 
Foul Air: 

Exhaust, BP No. 12 
Freezing: 

Protection from, 2.16 
Friction Loss Allowance 

Pipe, tube, and fittings, B.9.7 
Frost Closure: 

Vent terminals, 12.5 
Garage Can Washers: 

Requirements for, 7.17 
Grade: 

Definition of, 1.2 
Gray water Recycling Systems: 

Requirements for, Appendix G 
Grease Interceptors: 

Requirements for, 6.3 
Grease Recovery Devices (GRD): 

Requirements for, 6.3 
Ground Water: 

Definition of, 1.2 
Protection of, BP No. 22 
Hangers (pipe): 

Requirements for, Chapter 8 
Health Care Facilities: 
Aspirators, 14.13 
Bedpan Washers, 14.8 
Central vacuum systems, 14.12 
Clinical sinks, 14.8 
Local vents and stacks, 14.9 
Medical gas and vacuum systems, 14.3 
Mental pati ent rooms , 1 4 . 5 
Prohibited locations for ice storage, 14.6 



2006 National Standard Plumbing Code-Illustrated 



457 



Protrusions from walls, 14.4 
Special requirements for, Chapter 14 
Sterilizers, 14.10 
Vapor vents and stacks, 14. 1 1 
Water service, 14.2 
Health Hazard: 

Definition of, 1.2 
Abatement of, 2.5 
Horizontal Branch Drain: 

Definition of, 1.2 
Horizontal Pipe: 

Definition of, 1 .2 
Hot Water: 

Definition of, 1.2 

Mixed water temperature control, 10.15.6 

Plastic piping, 10.15.8 

Temperature maintenance, 10.15.2 

Thermal expansion control, 10.15.7 

Where required, 10.15.1 
Indirect Waste Connections: 

Definition of, 1.2 

Air conditioning equipment, 9.1.10 

Drinking fountains, 9.1 .9 

Fixture traps, 9.2.3 

Food handling areas, 9.1.5 

Medical equipment, 9.1.7 

Piping, 9.2 

Potable clear water waste, 9.1.8 

Receptors, 9.3 

Requirements for, 9.1 

Sterile equipment, 9.1.7 

Swimming pools, 9.1.11 

Walk-in coolers, 9.1.6 

Walk-in freezers, 9.1.6 

Water coolers, 9.1.9 
Indirect Waste Pipe: 

Definition of, 1.2 

Materials, 9.2.1 

Size, 9.2.2 
Indirect Waste Receptors: 

DFU values, 9.3.7 

Minimum pipe size, 9.3.6 

Open-hub drains, 9.3.5 

Prohibited locations, 9.3.3 

Standpipes, 9.3.4 

Strainers or baskets, 9.3.2 
Industrial Waste: 

Definition of, 1.2 



Insanitary: 

Definition of, 1.2 
Installation Practices : 

Plumbing systems, 2.8 
Installed: 

Definition of, 1.2 
Interceptor: 

Definition of, 1 .2 
Invert: 

Definition of, 1.2 
Laundry Sinks: 

Requirements for, 7.11.3 
Lavatories: 

Minimum number required, Table 7.21.1 

Requirements for, 7.6 
Leaders (rain water): 

Definition of, 1.2 

Requirements for, 13.4 

Sizing of, 13.6 
Local Ventilating Pipe: 

Definition, 1.2 
Main: 

Definition, 1 .2 
Manholes: 

Requirements for, 5.4.10 
May: 

Definition, 1.2 
Metric Conversion: 

Tables, Appendix C 
Mixed Water Temperature Control: 

Requirements for, 10.15.6 
Mobile Home Parks: 

Requirements for, Chapter 1 8 
Multiple Dwelling: 

Definition, 1 .2 
Neutralizing Tanks: 

Requirements for, 6.6 
Non-potable Water: 

Definition, 1.2 
Nuisance: 

Definition, 1 .2 
Obstruction to Flow: 

Drainage, 2.4.3 
Offset: 

Definition, 1.2 
Offsets (drainage piping) 

Sizing, 11.6 
Oil/Water Separators: 

Requirements for, 6.3 



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2006 National Standard Plumbing Code-Illustrated 



Overflows: 

Lavatories, 7.6.4 

Flush tanks, 7.19.3.d 

Water supply tanks, 10.8.3 
Ornamental Fountains 

Backflow protection, 7.18 
Percolation Test: 

Individual sewage disposal systems, 16.5 
Pipe Joints: 

Bending, 4.2. 19 

Brazed, 4.2.8 

Burned lead, 4.2.10 

Butt fusion, 4.2. 18 

Caulked, 4.2. 12 

Cement mortar, 4.2.9 

Different materials, 4.3 

Expansion, 4.2. 16 

Flared, 4.2.5 

Mechanical, 4.2. 11 

Mechanically formed tee, 4.2.8.3 

Mechanically crimped, 4.2.6 

In plastic pipe, 4.2.14 

Push on, 4.2.7 

Slip, 4.2. 15 

Soldered, 4.2.4 

Split couplings, 4.2. 17 

Threaded, 4.2.2 

Wiped, 4.2.3 
Piping Materials: 

Air conditioning condensate, 3 . 9 

Chemical wastes, 3.1 1 

Combustion equipment drains, 3.10 

Foundation drains, 3.8 

Potable water, 3.4 

Sanitary drainage, 3.5 

Special waste, 3.11 

Storm water, 3.7 

Subsoil drains, 3.8 

Vents, 3.6 
Plumbing: 

Definition, 1.2 
Plumbing Appliance: 

Definition, 1.2 
Plumbing Appurtenance: 

Definition, 1.2 
Plumbing Fixture: 

Definition, 1.2 
Plumbing Inspector: 

Definition, 1.2 



Plumbing System: 

Definition, 1.2 
Pollution: 

Definition, 1.2 

Water service near sources of, 10.6.2 
Potable Water: 

Definition, 1.2 
Pressure Balancing Valve: 

Definition, 1.2 
Prevent Contamination: 

From sewage, BP No. 15 
Private Sewage Disposal System: 
Definition, 1 .2 

Requirements for, Chapter 16 
Private Sewer: 

Definition of, 1.2 
Private Water Supply: 
Definition of, 1.2 
Prohibited Valves: 

Underground stop & waste, 10.6.3 
Public Sewer: 

Definition of, 1.2 
Public Toilet Room: 

Definition of, 1.2 
Public Water Main: 

Definition of, 1.2 
Public Sewer 

Definition of, 1.2 
Availability, 2. 19.1 
Basic principle, BP No. 6 
Public Water Main: 

Definition of, 1.2 
Availability, 2. 19.1 
Interconnections, 10.4.2 
Rainfall Rates: 

Appendix A 
Readily Accessible: 
Definition, 1.2 
Reduced Pressure Backflow Preventer: 
Definition, 1.2 
Installation of, 10. 5.5. d 
Maintenance of, 10.5.6 
Testing of, 10.5.6 
Where required, 10.5.3 
Rim: 

Definition, 1.2 
Riser: 

Definition, 1.2 



2006 National Standard Plumbing Code-Illustrated 



459 



Roof Drains: 

Definition, 1.2 

Requirements for, 13.5 
Roof Gutters: 

Sizing, 13.6.3 
Roughing-in: 

Definition of, 1.2 
Safety Devices: 

Combination P&T relief valves, 10.16.4 

Pressure relief valves, 10.16.2 

Relief valve discharge piping, 10.16.6 

Replacement of relief valves, 10.16.8 

Temperature relief valves, 10.16.3 

Thermal expansion control, 10. 1 5.7 

Vacuum relief valves, 10.16.7 
Sand Interceptors: 

Requirements for, 6.4 
Sanitary Sewer: 

Definition of, 1.2 
Seepage Pits: 

Absorption area for, 16.5.6 

Where contemplated, 16.5.5 
Septic Tanks: 

Definition of, 1.2 

Capacity of, 16.6 

Location of, 16.4.4 
Sewage: 

Definition of, 1.2 
Sewage Disposal Systems: 

Private, Chapter 16 
Sewage Ejectors, Pneumatic: 

Definition of, 1.2 

Vents, 11.7.7 
Sewage Pumps: 

Definition of, 1 .2 

Requirements for, 1 1.7 
Sewage Systems: 

Private, 2.19.2 
Shall: 

Definition of, 1.2 
Shock Arrestor: 

Definition of, 1.2 

Water hammer, 10.14.7 
Showers: 

Floors or receptors, 7.10.6 

Minimum number required, Table 7.21.1 

Mixed temperature control, 7. 10.3 

Shower compartments, 7.10.5 

Supply riser support, 7.10.7 



Waste outlet size, 7. 10.4 

Water conservation, 7.10.2 
Sinks: 

Bar sinks, 7.11.2 

Bedpan washers, 14.8.1 

Clinical sinks, 14.8.1 

Compliance, 7. 11.1 

Faucets, 7.11.5 

Kitchen sinks, 7.11.2 

Laundry sinks, 7.11.3 

Mop receptors, 7.1 1.4 

Service sinks, 7. 1 1 .4 
Sizing the Building Water Supply System: 

Appendix B 
Slaughterhouses: 

Drainage in, 6.7.3 
Sleeves: 

Pipe, 2.12 
Slope: 

See Grade 
SoilPipe: 

Definition, 1 .2 
Soil Stack: 

Definition, 1.2 
Solids Interceptors: 

Requirements for, 6.5 
Special Design Plumbing Systems: 

Appendix E 
Special Wastes: 

Definition, 1 .2 

Drain piping, 3. 11.1 

Treatment of, 9.4.1 

Vent piping, 3.11.2 
Stack (drainage): 

Definition, 1.2 

Size reduction, 1 1.5.7 
Stack Vent: 

Definition, 1 .2 

Where required, 12. 3. La 
Standard Dimensional Ratio (SDR): 

Definition of, 1 .2 

In plastic drainage piping, 3.5.4 
Sterilizers: 

Drainage of, 14.10 

Vapor vents and stacks, 14.1 1 
Storm Sewer: 

Definition, 1 .2 
Storm Water Drainage: 

Paved areas, 13.1.1 



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2006 National Standard Plumbing Code-Illustrated 



Strainers (for indirect waste): 

Where required, 9.3.2 
Subsoil Drain: 

Definition, 1 .2 
Suds Pressure Zones: 

Branch connections within, 11.11.1 

Exceptions to, 11.11.4 

Location of zones, 11.11.2 

Relief vents for, 12.15 

Separate stacks, 11.11.3 
Sump Pump: 

Definition, 1 .2 

Air conditioning condensate flow, 13.8 

For foundation drains, 13.1.5.d 
Sumps, Drainage (sewage): 

Definition, 1.2 

Venting, 12.14.2 
Supports: 

Definition, 1 .2 

Hangers and Supports, Chapter 8 
Swimming Pools: 

Definition of, 1.2 

Backflow prevention, 7.14 
Tanks: 

Dilution, 6.6 

Flush tanks, 

Flushometer tanks, 

Hot water, 3.3.8 

Neutralizing, 6.6 

Septic, 3.3.1 1,16.6 

Waste oil, 6.3 
Tempered Water: 

Definition, 1.2 
Thermal Expansion Control : 

For domestic hot water, 10.15.7 
ToiletFacilities: 

Definition, 1 .2 

For construction workers, 2.24 

Minimum number required, Table 7.21.1 
Toilet Rooms: 

Requirements for, 2.20 
Trap Arms: 

Definition, 1 .2 

Maximum length of, 12.8. 1 
Trap Seal: 

Definition, 1.2 

Required depth, 5.3.2 
Traps: 

Definitions, 1 .2 



Design, 5.3.1 

Level setting, 5.3.3 

Protection from freezing, 5.3.3 

Required size, 5.2 
Travel trailer Parks: 

Requirements for, Chapter 18 
Trenching: 

Bedding, 2.6.1 

Copperpiping, 2.6.7 

Final backfill, 2.6.4 

Initial backfill, 2.6.3 

Plasticpipe,2.6.6 

Requirements for, 2.6.1 

Safety, 2.6.8 

Side fill, 2.6.2 

Supervision, 2.6.9 
Trenchless Pipe Replacement 

Requirements for, 2.6. 10 
Tunneling: 

Pipe installation, 2.6.5 
Urinals: 

Compliance, 7.5.1 

Prohibited types, 7.5.4 

Surrounding surfaces, 7.5.3 

Water conservation, 7.5.2 
Vacuum Breakers: 

For backflow prevention, 10.5.3 

For lawn sprinkler systems, 10.5.10 

For hose connections, 10.5.12 

For irrigation systems, 10.5.10 

For special equipment, 10.5.13 

Installation of, 10.5.5 

Maintenance of, 10.5.6 

Testing, 10.5.6 
Vacuum Systems: 

Draining, 14.12 
Valves: 

Access to, 10.12.9 

Anti-scald, 10.15.6 

Backwater, 5.5 

Building, 10.12.2 

Curb, 10.12.1 

Double check, 10.5.3 

Flushometer, 7.19.5 

For individual fixtures, 10.12.6 

In dwelling units, 10.12.4 

Mixed water temperature, 10.15.6 

P&T relief, 10.16.4 

Pressure reducing, 10.14.6 



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461 



Pressure relief, 10.16 

Riser shutoff, 10.12.5 

Temperature relief, 10.16 

Water heater shutoff, 10.12.7 
Velocity Limitations : 

In copper tubing, B.6.3 

In water piping, 10.14.1 
Vent Piping Systems: 

Aggregate size of terminals, 12.16.6 

Circuit venting, 12.13 

Combination waste & vent, 12.17 

Common vents, 12.9 

Extension above roofs, 12.4. 1 

Extensions outside ofbuildings, 12.4.6 

Fixture reventing, 12.12 

Fixtures connected at different levels, 12.9.2 

For building subdrain systems, 12. 14 

For horizontal stack offsets, 12.3.3 

For pneumatic sewage ejectors, 12.14.3 

For sump pits, 12.14.2 

Frost closure, 12.5 

Height of connections, 12.6.3 

Island sink venting, 12.18 

Individual vents, 12.9.1 

Length of vents, 12.16 

Location of vent terminals, 12.4.4 

Loop venting, 12.13 

Materials, 3.6 

Other designs, 12.19 

Pipe size, 12.16 

Pipe slope, 12.6.1 

Prohibited use, 12.3.6, 12.4.3 

Protection of trap seals, 12.2 

Relief vents for stacks, 12.3.2 

Sidewall venting, 12.4.5 

Stack vent size, 12.16.4 

Suds pressure venting, 12.15 

Test methods, 15.4 

Underground piping, 12.16.7 

Vent headers, 12.16.5 

Vent stack size, 12.16.4 

Vent washdown, 12.12.4 

Waterproof roof flashings, 12.4.2 

Wet venting, 12.10 
Wading Pools: 

Backflow prevention, 7.14 
Washrooms: 

Requirements for, 2.20 



Waste: 

Definition, 1.2 

Industrial,2.10.2 

Potable clear water, 9.1.8 

Special, 9.4 
Waste Pipe: 

Definition, 1.2 

Sizes, 11.5 
Water Distribution Piping : 

Definition, 1.2 

Backflow prevention, 10.5 

Basic design circuit (BDC), B.9.3 

Control valves, 10.12 

Disinfecting, 10.9.2 

Excessive pressure, 10.14.6 

Flushing, 10.9.1 

Identify non-potable & potable, 10.2 

Inadequate water pressure, 10.14.4 

Materials, 3.4 

Maximum velocity, 10.14.1,B6 

Minimum requirements for, 10.14 

Pressure booster systems, 10.8 

Protection of, 10.4 

Sizing, 10.14.3 

Variable street pressures, 10.14.5 

Water hammer, 10.14.7 

Water quality, 10.1 

Water service, 10.6 
Water Hammer: 

Arrestors, 10.14.7 
Water Heaters: 

Drainage from, 10.15.4 

Minimum requirements for, 10.15.3 

Pressure marking of, 10.15.5 

Safety devices for, 10.16 

Used for space heating, 10.15.10 
Water Pipe Friction: 

Limitations, B. 9 
Water Pressure: 

Excessive, 10.14.6 

Inadequate, 10.14.4 

Minimum required, 10.14.2 

Minimum street, 10.14.5 
Water Pressure Booster Systems: 

Requirements for, 10.8 

Where required, 10.8.1 
Water Pressure Tanks: 
Construction, 3.3.8 



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2006 National Standard Plumbing Code-Illustrated 



Drains for, 10.8.6 
Pressure relief, 10.8.9 
Safety devices for, 3.3.10 
Waterfalls: 

Backflow prevention, 7.14 



2006 National Standard Plumbing Code-Illustrated -—>•—- 



NOTES 



464 2006 National Standard Plumbing Code-Illustrated